release: publish Twitch VOD Manager 1.0.5

CHANGELOG.md

@@ -1,5 +1,15 @@
 # Changelog
 
+## 1.0.5 - 2026-08-11
+
+- Added a complete local video editor for MP4, M4V, MOV, WebM, MKV, TS and AVI files with frame-accurate trimming, removable ranges, undo and redo, timeline zoom and atomic exports.
+- Added a responsive desktop player with smooth scrubbing, keyboard controls, volume interaction, fullscreen playback and synchronized playback state.
+- Added high-resolution video thumbnails and a reusable waveform timeline that remain sharp across zoom levels without blocking the first usable view.
+- Added precise timeline handles, mouse-wheel zoom anchored to the pointer and smooth navigation for short and long recordings.
+- Added safe source validation, cancellable exports and protection against partial or overwritten output files.
+- Added a confirmation step before replacing an active edit and reset playback controls correctly when another video is opened.
+- Improved editor layout, timestamp readability, metadata alignment, action contrast and language-selection contrast across supported window sizes.
+
 ## 1.0.4 - 2026-08-11
 
 - Added smooth entrance and exit motion for the VOD selection action dock, including Windows systems with reduced animations enabled.

README.md

@@ -33,7 +33,8 @@ The application works in public mode without a Twitch login. Connecting a Twitch
 ### Download and process
 
 - Download complete VODs or selected time ranges
-- Trim, split and merge recordings with dedicated tools
+- Edit local videos with frame-accurate trimming, removable ranges, timeline zoom, waveform guidance and undo or redo
+- Split and merge recordings with dedicated tools
 - Queue multiple jobs and follow real progress, speed and remaining time
 - Pause and continue an active download without restarting it
 - Save optional chat replays and stream events alongside recordings
@@ -60,7 +61,7 @@ The application works in public mode without a Twitch login. Connecting a Twitch
 ## Installation
 
 1. Open the [latest GitHub release](https://github.com/Sucukdeluxe/Twitch-VOD-Manager/releases/latest).
-2. Download `Twitch-VOD-Manager-Setup-1.0.4.exe`.
+2. Download `Twitch-VOD-Manager-Setup-1.0.5.exe`.
 3. Run the installer and choose the installation directory.
 4. Start Twitch VOD Manager and add a streamer.
 

package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "twitch-vod-manager",
-  "version": "1.0.4",
+  "version": "1.0.5",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "twitch-vod-manager",
-      "version": "1.0.4",
+      "version": "1.0.5",
       "license": "MIT",
       "dependencies": {
         "axios": "^1.16.1",

package.json

@@ -1,6 +1,6 @@
 {
   "name": "twitch-vod-manager",
-  "version": "1.0.4",
+  "version": "1.0.5",
   "description": "Twitch VOD Manager - Download Twitch VODs easily",
   "main": "dist/main.js",
   "author": "Sucukdeluxe",
@@ -20,9 +20,10 @@
     "test:e2e:guide": "node scripts/smoke-test-template-guide.js",
     "test:e2e:full": "node scripts/smoke-test-full.js",
     "test:e2e:workspace-ui": "npm run build && node scripts/smoke-test-workspace-ui.js",
+    "test:e2e:cutter": "npm run build && node scripts/smoke-test-cutter.js",
     "test:e2e:isolation": "node scripts/smoke-test-e2e-isolation-contract.js",
     "test:e2e:settings-autosave": "node scripts/smoke-test-settings-autosave.js",
-    "test:e2e:release": "npm run build && npm run test:unit && npm run test:e2e:update-logic && npm run test:merge-split && npm run test:e2e:public-release && npm run test:e2e:workspace-ui && npm run test:e2e:isolation && npm run test:e2e && npm run test:e2e:guide && npm run test:e2e:full && npm run test:e2e:settings-autosave",
+    "test:e2e:release": "npm run build && npm run test:unit && npm run test:e2e:update-logic && npm run test:merge-split && npm run test:e2e:public-release && npm run test:e2e:workspace-ui && node scripts/smoke-test-cutter.js && npm run test:e2e:isolation && npm run test:e2e && npm run test:e2e:guide && npm run test:e2e:full && npm run test:e2e:settings-autosave",
     "test:e2e:stress": "npm run test:e2e:release && npm run test:e2e:release && npm run test:e2e:release",
     "pack": "npm run build && electron-builder --dir",
     "dist": "npm run build && electron-builder",

scripts/dev.mjs

@@ -83,7 +83,7 @@ if (process.platform === 'win32') {
         sourcePath: electronSourceExecutable,
         destinationPath: resolve(rootDirectory, 'node_modules', 'electron', 'dist', 'Twitch VOD Manager.exe'),
         iconPath: resolve(rootDirectory, 'build', 'icon.ico'),
-        version: '1.0.4',
+        version: '1.0.5',
     });
 }
 

scripts/public-release-files.json

@@ -15,6 +15,7 @@
     "scripts/capture-readme-screenshot.js",
     "scripts/dev.mjs",
     "scripts/public-release-files.json",
+    "scripts/smoke-test-cutter.js",
     "scripts/smoke-test-e2e-isolation-contract.js",
     "scripts/smoke-test-full.js",
     "scripts/smoke-test-merge-split-logic.js",
@@ -31,6 +32,8 @@
     "src/main/domain/chunk-index-store.ts",
     "src/main/domain/config-normalize.test.ts",
     "src/main/domain/config-normalize.ts",
+    "src/main/domain/cutter-export.test.ts",
+    "src/main/domain/cutter-export.ts",
     "src/main/domain/app-identity.test.ts",
     "src/main/domain/app-identity.ts",
     "src/main/domain/i18n-backend.test.ts",
@@ -55,6 +58,8 @@
     "src/main/domain/twitch-oauth.ts",
     "src/main/domain/update-version-utils.test.ts",
     "src/main/domain/update-version-utils.ts",
+    "src/main/domain/video-editor.test.ts",
+    "src/main/domain/video-editor.ts",
     "src/main/index.ts",
     "src/main/infra/chunk-hash.test.ts",
     "src/main/infra/chunk-hash.ts",
@@ -79,6 +84,7 @@
     "src/preload.ts",
     "src/renderer-archive.ts",
     "src/renderer-command-palette.ts",
+    "src/renderer-cutter.ts",
     "src/renderer-globals.d.ts",
     "src/renderer-locale-de.ts",
     "src/renderer-locale-en.ts",

scripts/smoke-test-public-release-config.js

@@ -14,9 +14,9 @@ function check(condition, message) {
   if (!condition) failures.push(message);
 }
 
-check(packageJson.version === '1.0.4', `package version is ${packageJson.version}`);
+check(packageJson.version === '1.0.5', `package version is ${packageJson.version}`);
-check(packageLock.version === '1.0.4', `lockfile version is ${packageLock.version}`);
+check(packageLock.version === '1.0.5', `lockfile version is ${packageLock.version}`);
-check(packageLock.packages?.['']?.version === '1.0.4', `lockfile root package version is ${packageLock.packages?.['']?.version}`);
+check(packageLock.packages?.['']?.version === '1.0.5', `lockfile root package version is ${packageLock.packages?.['']?.version}`);
 check(packageJson.build?.appId === 'io.github.sucukdeluxe.twitch-vod-manager', `appId is ${packageJson.build?.appId}`);
 check(packageJson.build?.publish?.provider === 'generic', `publish provider is ${packageJson.build?.publish?.provider}`);
 check(packageJson.build?.publish?.url === 'https://github.com/Sucukdeluxe/Twitch-VOD-Manager/releases/latest/download/', `publish URL is ${packageJson.build?.publish?.url}`);
@@ -45,7 +45,7 @@ check(mainSource.includes('GITHUB_RELEASES_DOWNLOAD_BASE_URL'), 'GitHub releases
 check(mainSource.includes('https://api.github.com/repos/Sucukdeluxe/Twitch-VOD-Manager/releases/latest'), 'GitHub latest release API URL is missing');
 check(mainSource.includes('https://github.com/Sucukdeluxe/Twitch-VOD-Manager/releases/download'), 'GitHub release download URL is missing');
 check(!/storyboards\/\d{8,12}(?:-|\/)/.test(mainSource), 'numeric Twitch VOD example remains in the public source');
-check(indexSource.includes('Version: v1.0.4'), 'initial version label is not 1.0.4');
+check(indexSource.includes('Version: v1.0.5'), 'initial version label is not 1.0.5');
 check(!indexSource.includes('Version: v4.1.13'), 'legacy version label is still present');
 check(fs.existsSync(manifestPath), 'public release manifest is missing');
 

scripts/smoke-test-workspace-ui.js

@@ -96,6 +96,31 @@ async function run() {
     check(shell.topNavigationItems === 7, `Expected 7 native primary navigation buttons, found ${shell.topNavigationItems}`);
     check(shell.nonButtonNavigationItems === 0, `Expected only native primary navigation buttons, found ${shell.nonButtonNavigationItems} non-buttons`);
 
+    const mergeAddToolbarActions = await win.evaluate(() => {
+      const capture = () => {
+        const button = document.querySelector('[data-toolbar-for="merge"] button[onclick="addMergeFiles()"]');
+        const label = button?.querySelector('span')?.textContent?.trim() || '';
+        const accessibleLabel = button?.getAttribute('aria-label')?.trim() || label;
+        return {
+          label,
+          accessibleLabel,
+          plusCount: (button?.querySelectorAll('svg').length || 0) + ((button?.textContent?.match(/\+/g) || []).length)
+        };
+      };
+
+      window.changeLanguage('en');
+      const english = capture();
+      window.changeLanguage('de');
+      const german = capture();
+      window.changeLanguage('en');
+      return { english, german };
+    });
+    checks.mergeAddToolbarActions = mergeAddToolbarActions;
+    check(mergeAddToolbarActions.english.plusCount === 1, `English Add videos toolbar action exposes ${mergeAddToolbarActions.english.plusCount} plus signs`);
+    check(mergeAddToolbarActions.german.plusCount === 1, `German Videos hinzufügen toolbar action exposes ${mergeAddToolbarActions.german.plusCount} plus signs`);
+    check(mergeAddToolbarActions.english.label === 'Add videos' && mergeAddToolbarActions.english.accessibleLabel === 'Add videos', `English Add videos toolbar label is "${mergeAddToolbarActions.english.accessibleLabel}"`);
+    check(mergeAddToolbarActions.german.label === 'Videos hinzufügen' && mergeAddToolbarActions.german.accessibleLabel === 'Videos hinzufügen', `German Videos hinzufügen toolbar label is "${mergeAddToolbarActions.german.accessibleLabel}"`);
+
     await app.evaluate(({ ipcMain }) => {
       globalThis.__workspaceStreamerCacheCalls = { ids: 0, vods: 0, profiles: 0 };
       ipcMain.removeHandler('get-user-id');
@@ -152,16 +177,16 @@ async function run() {
     const cutterDropFixturePath = path.join(environment.mediaDir, 'electron-43-cutter-drop.mp4');
     fs.writeFileSync(cutterDropFixturePath, 'electron-43-cutter-drop-fixture', 'utf8');
     await app.evaluate(({ ipcMain }) => {
-      globalThis.__workspaceCutterDropPaths = { videoInfo: '', preview: '' };
+      globalThis.__workspaceCutterDropPaths = { media: '' };
-      ipcMain.removeHandler('get-video-info');
+      ipcMain.removeHandler('prepare-video-editor-media');
-      ipcMain.handle('get-video-info', (_, filePath) => {
+      ipcMain.handle('prepare-video-editor-media', (_, filePath) => {
-        globalThis.__workspaceCutterDropPaths.videoInfo = filePath;
+        globalThis.__workspaceCutterDropPaths.media = filePath;
-        return { duration: 120, width: 1920, height: 1080, fps: 60 };
+        return {
-      });
+          sourceUrl: encodeURI(`file:///${filePath.replace(/\\/g, '/')}`),
-      ipcMain.removeHandler('extract-frame');
+          info: { duration: 120, width: 1920, height: 1080, fps: 60, hasAudio: false },
-      ipcMain.handle('extract-frame', (_, filePath) => {
+          thumbnails: ['data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///ywAAAAAAQABAAACAUwAOw=='],
-        globalThis.__workspaceCutterDropPaths.preview = filePath;
+          waveform: null
-        return null;
+        };
       });
     });
     await win.evaluate(() => {
@@ -205,8 +230,7 @@ async function run() {
     };
     check(cutterFileObject.legacyPathType === 'undefined', `Electron File.path is unexpectedly ${cutterFileObject.legacyPathType}`);
     check(cutterDropUi.filePath === cutterDropFixturePath, `Cutter drop resolved "${cutterDropUi.filePath}" instead of the Electron file path`);
-    check(cutterDropPaths.videoInfo === cutterDropFixturePath, `Cutter drop sent "${cutterDropPaths.videoInfo}" to video info instead of the Electron file path`);
+    check(cutterDropPaths.media === cutterDropFixturePath, `Cutter drop sent "${cutterDropPaths.media}" to media preparation instead of the Electron file path`);
-    check(cutterDropPaths.preview === cutterDropFixturePath, `Cutter drop sent "${cutterDropPaths.preview}" to preview instead of the Electron file path`);
     check(cutterDropUi.infoVisible && cutterDropUi.cutEnabled, 'Cutter drop did not populate the cutter controls');
 
     const queueEmptyActions = await win.evaluate(() => ({
@@ -1625,6 +1649,8 @@ async function run() {
       const germanLabelBlendAtMiddle = getComputedStyle(document.getElementById('languageDeText')).mixBlendMode;
       await pause(420);
       const target = readX();
+      const germanLabelColorSelected = getComputedStyle(document.getElementById('languageDeText')).color;
+      const englishLabelColorInactive = getComputedStyle(document.getElementById('languageEnText')).color;
       window.changeLanguage('en');
       await pause(150);
       const reverseMiddle = readX();
@@ -1644,6 +1670,8 @@ async function run() {
         targetBackgroundAtMiddle,
         englishLabelBlendAtMiddle,
         germanLabelBlendAtMiddle,
+        germanLabelColorSelected,
+        englishLabelColorInactive,
         transformRuns,
         transition: getComputedStyle(picker, '::before').transition
       };
@@ -1659,7 +1687,8 @@ async function run() {
     check(languageSwitcherMotion.reverseMiddle > languageMotionMinimum + 1 && languageSwitcherMotion.reverseMiddle < languageMotionMaximum - 1, 'Language marker has no visible reverse intermediate position');
     check(Math.abs(languageSwitcherMotion.reverseTarget - languageSwitcherMotion.start) < 1, 'Language marker does not return to English');
     check(languageSwitcherMotion.targetBackgroundAtMiddle === 'rgba(0, 0, 0, 0)', `Language target paints a second background during motion: ${languageSwitcherMotion.targetBackgroundAtMiddle}`);
-    check(languageSwitcherMotion.englishLabelBlendAtMiddle === 'difference' && languageSwitcherMotion.germanLabelBlendAtMiddle === 'difference', `Language labels do not adapt continuously to the moving marker: ${languageSwitcherMotion.englishLabelBlendAtMiddle}/${languageSwitcherMotion.germanLabelBlendAtMiddle}`);
+    check(languageSwitcherMotion.englishLabelBlendAtMiddle === 'normal' && languageSwitcherMotion.germanLabelBlendAtMiddle === 'normal', `Language labels still use color-distorting blend modes: ${languageSwitcherMotion.englishLabelBlendAtMiddle}/${languageSwitcherMotion.germanLabelBlendAtMiddle}`);
+    check(languageSwitcherMotion.germanLabelColorSelected === 'rgb(23, 32, 51)' && languageSwitcherMotion.englishLabelColorInactive === 'rgb(173, 169, 169)', `Selected and inactive language labels do not use the requested contrast: ${languageSwitcherMotion.germanLabelColorSelected}/${languageSwitcherMotion.englishLabelColorInactive}`);
     await win.evaluate(() => window.changeLanguage('en'));
     await win.waitForTimeout(460);
     await win.evaluate(() => window.changeLanguage('de'));

src/index.html

@@ -3,7 +3,7 @@
 <head>
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
-    <meta http-equiv="Content-Security-Policy" content="default-src 'self'; script-src 'self' 'unsafe-inline'; style-src 'self' 'unsafe-inline'; img-src 'self' https: data:;">
+    <meta http-equiv="Content-Security-Policy" content="default-src 'self'; script-src 'self' 'unsafe-inline'; style-src 'self' 'unsafe-inline'; img-src 'self' https: data: blob:; media-src 'self' file: blob:;">
     <title>Twitch VOD Manager</title>
     <link rel="stylesheet" href="./styles.css">
     <link rel="stylesheet" href="./workspace.css">
@@ -36,6 +36,17 @@
         </div>
     </div>
 
+    <div class="modal-overlay" id="cutterDiscardModal" role="dialog" aria-modal="true" aria-hidden="true" aria-labelledby="cutterDiscardTitle" onclick="handleCutterDiscardOverlayClick(event)" onkeydown="trapCutterDiscardFocus(event)">
+        <div class="modal cutter-discard-modal">
+            <h2 id="cutterDiscardTitle">Aktuellen Schnitt verwerfen?</h2>
+            <p id="cutterDiscardMessage">Beim Öffnen eines anderen Videos gehen die aktuellen Schnittänderungen verloren.</p>
+            <div class="modal-actions">
+                <button class="btn-secondary" id="cutterDiscardCancelBtn" type="button" onclick="resolveCutterDiscard(false)">Aktuelles Video behalten</button>
+                <button class="btn-danger" id="cutterDiscardConfirmBtn" type="button" onclick="resolveCutterDiscard(true)">Verwerfen und öffnen</button>
+            </div>
+        </div>
+    </div>
+
     <!-- Clip Dialog Modal -->
     <div class="modal-overlay" id="clipModal" role="dialog" aria-modal="true" aria-labelledby="clipDialogTitle">
         <div class="modal clip-modal">
@@ -436,54 +447,163 @@
                 <!-- Video Cutter Tab -->
                 <div class="tab-content" id="cutterTab">
                     <div class="cutter-container">
-                        <div class="settings-card">
+                        <div class="cutter-source-bar">
-                            <h3 id="cutterSelectTitle">Video auswählen</h3>
+                            <div class="cutter-source-copy">
-                            <div class="form-row">
+                                <span class="cutter-source-title" id="cutterSelectTitle">Video auswählen</span>
-                                <input type="text" id="cutterFilePath" readonly placeholder="Keine Datei ausgewahlt...">
+                                <input type="text" id="cutterFilePath" readonly aria-labelledby="cutterSelectTitle" placeholder="Keine Datei ausgewählt…">
-                                <button type="button" class="btn-secondary" id="cutterBrowseBtn" onclick="selectCutterVideo()">Durchsuchen</button>
                             </div>
+                            <button type="button" class="btn-secondary" id="cutterBrowseBtn" onclick="selectCutterVideo()">Durchsuchen</button>
                         </div>
 
-                        <div class="video-preview" id="cutterPreview">
+                        <div class="cutter-workspace" id="cutterWorkspace">
-                            <div class="placeholder">
+                            <aside class="cutter-sidebar">
-                                <svg aria-hidden="true" width="64" height="64" viewBox="0 0 24 24" fill="currentColor"><path d="M21 3H3c-1.1 0-2 .9-2 2v14c0 1.1.9 2 2 2h18c1.1 0 2-.9 2-2V5c0-1.1-.9-2-2-2zm0 16H3V5h18v14zM9 8l7 4-7 4V8z"/></svg>
+                                <div class="cutter-sidebar-heading">
-                                <p id="cutterPreviewPlaceholder">Video auswählen um Vorschau zu sehen</p>
+                                    <div>
-                            </div>
+                                        <span class="cutter-eyebrow">EDITOR</span>
-                        </div>
+                                        <h3 id="cutterEditHeading">Trimmen & schneiden</h3>
+                                    </div>
+                                    <button type="button" class="cutter-icon-button" id="cutterNewCutBtn" onclick="addCutterCut()" disabled aria-label="Neuer Schnitt" title="Neuer Schnitt">
+                                        <svg aria-hidden="true" viewBox="0 0 24 24"><path d="M12 5v14M5 12h14"></path></svg>
+                                    </button>
+                                </div>
+                                <label class="cutter-preview-toggle">
+                                    <span>
+                                        <strong id="cutterPreviewModeLabel">Schnittvorschau</strong>
+                                        <small id="cutterPreviewModeHint">Entfernte Bereiche überspringen</small>
+                                    </span>
+                                    <input type="checkbox" id="cutterPreviewMode" checked onchange="setCutterPreviewMode(this.checked)">
+                                    <span class="cutter-toggle-track" aria-hidden="true"></span>
+                                </label>
+                                <div class="cutter-trim-card">
+                                    <div class="cutter-card-title" id="cutterGlobalTrimLabel">Gesamtauswahl</div>
+                                    <div class="cutter-time-field-row">
+                                        <label for="startTime" id="cutterStartLabel">Start</label>
+                                        <input type="text" id="startTime" value="00:00:00" spellcheck="false" onchange="updateTimeFromInput()">
+                                    </div>
+                                    <div class="cutter-time-field-row">
+                                        <label for="endTime" id="cutterEndLabel">Ende</label>
+                                        <input type="text" id="endTime" value="00:00:00" spellcheck="false" onchange="updateTimeFromInput()">
+                                    </div>
+                                </div>
+                                <div class="cutter-cut-section">
+                                    <div class="cutter-card-title-row">
+                                        <span class="cutter-card-title" id="cutterCutsLabel">Entfernte Bereiche</span>
+                                        <span class="cutter-cut-count" id="cutterCutCount">0</span>
+                                    </div>
+                                    <div class="cutter-cut-list" id="cutterCutList">
+                                        <div class="cutter-cut-empty" id="cutterCutEmpty">Noch keine Schnitte</div>
+                                    </div>
+                                </div>
+                            </aside>
 
-                        <div class="cutter-info" id="cutterInfo">
+                            <section class="cutter-preview-panel">
-                            <div class="cutter-info-item">
+                                <div class="video-preview" id="cutterPreview">
-                                <span class="cutter-info-label" id="cutterInfoDurationLabel">Dauer</span>
+                                    <video id="cutterVideo" preload="metadata"></video>
-                                <span class="cutter-info-value" id="infoDuration">--:--:--</span>
+                                    <div class="placeholder" id="cutterPreviewEmpty">
-                            </div>
+                                        <svg aria-hidden="true" width="64" height="64" viewBox="0 0 24 24" fill="currentColor"><path d="M21 3H3c-1.1 0-2 .9-2 2v14c0 1.1.9 2 2 2h18c1.1 0 2-.9 2-2V5c0-1.1-.9-2-2-2zm0 16H3V5h18v14zM9 8l7 4-7 4V8z"/></svg>
-                            <div class="cutter-info-item">
+                                        <p id="cutterPreviewPlaceholder">Video auswählen, um eine Vorschau zu sehen</p>
-                                <span class="cutter-info-label" id="cutterInfoResolutionLabel">Auflösung</span>
+                                    </div>
-                                <span class="cutter-info-value" id="infoResolution">----x----</span>
+                                    <div class="cutter-player-loading" id="cutterPlayerLoading" hidden>
-                            </div>
+                                        <span class="cutter-spinner"></span>
-                            <div class="cutter-info-item">
+                                        <span id="cutterLoadingLabel">Video wird vorbereitet…</span>
-                                <span class="cutter-info-label" id="cutterInfoFpsLabel">FPS</span>
+                                    </div>
-                                <span class="cutter-info-value" id="infoFps">--</span>
+                                    <div class="cutter-player-controls" id="cutterPlayerControls">
-                            </div>
+                                        <button type="button" class="cutter-player-button" id="cutterPlayBtn" onclick="toggleCutterPlayback()" disabled aria-label="Abspielen">
-                            <div class="cutter-info-item">
+                                            <svg class="cutter-play-icon" aria-hidden="true" viewBox="0 0 24 24"><path d="M8 5v14l11-7z"></path></svg>
-                                <span class="cutter-info-label" id="cutterInfoSelectionLabel">Auswahl</span>
+                                            <svg class="cutter-pause-icon" aria-hidden="true" viewBox="0 0 24 24"><path d="M7 5h4v14H7zM13 5h4v14h-4z"></path></svg>
-                                <span class="cutter-info-value" id="infoSelection">--:--:--</span>
+                                        </button>
-                            </div>
+                                        <button type="button" class="cutter-player-button" id="cutterStopBtn" onclick="stopCutterPlayback()" disabled data-cutter-media-control aria-label="Stopp">
+                                            <svg class="cutter-filled-icon" aria-hidden="true" viewBox="0 0 24 24"><path d="M7 7h10v10H7z"></path></svg>
+                                        </button>
+                                        <button type="button" class="cutter-player-button cutter-skip-button" id="cutterRewindBtn" onclick="skipCutterPlayback(-10)" disabled data-cutter-media-control aria-label="10 Sekunden zurück">
+                                            <svg aria-hidden="true" viewBox="0 0 24 24"><path d="M5.2 8.2A8 8 0 1 1 4 14.5"></path><path d="M5 4v5h5"></path></svg><span>10</span>
+                                        </button>
+                                        <button type="button" class="cutter-player-button cutter-skip-button" id="cutterForwardBtn" onclick="skipCutterPlayback(10)" disabled data-cutter-media-control aria-label="10 Sekunden vor">
+                                            <svg aria-hidden="true" viewBox="0 0 24 24"><path d="M18.8 8.2A8 8 0 1 0 20 14.5"></path><path d="M19 4v5h-5"></path></svg><span>10</span>
+                                        </button>
+                                        <div class="cutter-volume-control">
+                                            <button type="button" class="cutter-player-button" id="cutterMuteBtn" onclick="toggleCutterMute()" disabled aria-label="Ton umschalten">
+                                                <svg aria-hidden="true" viewBox="0 0 24 24"><path d="M4 9v6h4l5 4V5L8 9H4zm12.5 3a4 4 0 0 0-2-3.46v6.92A4 4 0 0 0 16.5 12z"></path></svg>
+                                            </button>
+                                            <input type="range" class="cutter-volume" id="cutterVolume" min="0" max="1" step="0.05" value="1" disabled aria-label="Lautstärke">
+                                        </div>
+                                        <span class="cutter-player-time"><span id="cutterCurrentTime">00:00:00</span><span>/</span><span id="cutterTotalTime">00:00:00</span></span>
+                                        <select id="cutterPlaybackRate" hidden disabled aria-label="Wiedergabegeschwindigkeit">
+                                            <option value="0.5">0,5×</option>
+                                            <option value="0.75">0,75×</option>
+                                            <option value="1" selected>1×</option>
+                                            <option value="1.25">1,25×</option>
+                                            <option value="1.5">1,5×</option>
+                                            <option value="2">2×</option>
+                                        </select>
+                                        <div class="cutter-player-settings">
+                                            <button type="button" class="cutter-player-button" id="cutterSettingsBtn" onclick="toggleCutterSettingsMenu()" disabled aria-label="Einstellungen" aria-expanded="false">
+                                                <svg class="cutter-filled-icon" aria-hidden="true" viewBox="0 0 24 24"><path d="M19.4 13a7.8 7.8 0 0 0 .1-1 7.8 7.8 0 0 0-.1-1l2.1-1.6-2-3.4-2.5 1a8 8 0 0 0-1.7-1L15 3.3h-4L10.6 6a8 8 0 0 0-1.7 1L6.4 6l-2 3.4L6.5 11a7.8 7.8 0 0 0-.1 1 7.8 7.8 0 0 0 .1 1l-2.1 1.6 2 3.4 2.5-1a8 8 0 0 0 1.7 1l.4 2.7h4l.4-2.7a8 8 0 0 0 1.7-1l2.5 1 2-3.4L19.4 13zM13 15.5A3.5 3.5 0 1 1 13 8a3.5 3.5 0 0 1 0 7.5z"></path></svg>
+                                            </button>
+                                            <div class="cutter-settings-menu" id="cutterSettingsMenu" hidden>
+                                                <span id="cutterSpeedLabel">Geschwindigkeit</span>
+                                                <div class="cutter-speed-options">
+                                                    <button type="button" data-rate="0.5" onclick="setCutterPlaybackRate(0.5)">0,5×</button>
+                                                    <button type="button" data-rate="0.75" onclick="setCutterPlaybackRate(0.75)">0,75×</button>
+                                                    <button type="button" class="active" data-rate="1" onclick="setCutterPlaybackRate(1)">Normal</button>
+                                                    <button type="button" data-rate="1.25" onclick="setCutterPlaybackRate(1.25)">1,25×</button>
+                                                    <button type="button" data-rate="1.5" onclick="setCutterPlaybackRate(1.5)">1,5×</button>
+                                                    <button type="button" data-rate="2" onclick="setCutterPlaybackRate(2)">2×</button>
+                                                </div>
+                                            </div>
+                                        </div>
+                                        <button type="button" class="cutter-player-button" id="cutterFullscreenBtn" onclick="toggleCutterFullscreen()" disabled aria-label="Vollbild">
+                                            <svg aria-hidden="true" viewBox="0 0 24 24"><path d="M4 9V4h5M15 4h5v5M20 15v5h-5M9 20H4v-5"></path></svg>
+                                        </button>
+                                    </div>
+                                </div>
+
+                                <div class="cutter-info" id="cutterInfo">
+                                    <div class="cutter-info-item"><span class="cutter-info-label" id="cutterInfoDurationLabel">Dauer</span><span class="cutter-info-value" id="infoDuration">--:--:--</span></div>
+                                    <div class="cutter-info-item"><span class="cutter-info-label" id="cutterInfoResolutionLabel">Auflösung</span><span class="cutter-info-value" id="infoResolution">----×----</span></div>
+                                    <div class="cutter-info-item"><span class="cutter-info-label" id="cutterInfoFpsLabel">FPS</span><span class="cutter-info-value" id="infoFps">--</span></div>
+                                    <div class="cutter-info-item"><span class="cutter-info-label" id="cutterInfoSelectionLabel">Ausgabe</span><span class="cutter-info-value" id="infoSelection">--:--:--</span></div>
+                                </div>
+                            </section>
                         </div>
 
                         <div class="timeline-container" id="timelineContainer">
-                            <div class="timeline" id="timeline" onclick="seekTimeline(event)">
+                            <div class="cutter-timeline-toolbar">
-                                <div class="timeline-selection" id="timelineSelection"></div>
+                                <div class="cutter-timeline-timecode" id="cutterTimelineTimecode">00:00:00</div>
-                                <div class="timeline-current" id="timelineCurrent"></div>
+                                <div class="cutter-history-controls">
-                            </div>
+                                    <button type="button" class="cutter-icon-button" id="cutterUndoBtn" onclick="undoCutterEdit()" disabled aria-label="Rückgängig" title="Rückgängig (Strg+Z)"><svg aria-hidden="true" viewBox="0 0 24 24"><path d="M9 7 4 12l5 5v-3h5a5 5 0 0 1 5 5v1h2v-1a7 7 0 0 0-7-7H9V7z"></path></svg></button>
-
+                                    <button type="button" class="cutter-icon-button" id="cutterRedoBtn" onclick="redoCutterEdit()" disabled aria-label="Wiederholen" title="Wiederholen (Strg+Y)"><svg aria-hidden="true" viewBox="0 0 24 24"><path d="m15 7 5 5-5 5v-3h-5a5 5 0 0 0-5 5v1H3v-1a7 7 0 0 1 7-7h5V7z"></path></svg></button>
-                            <div class="time-inputs">
-                                <div class="time-input-group">
-                                    <label id="cutterStartLabel" for="startTime">Start:</label>
-                                    <input type="text" id="startTime" value="00:00:00" onchange="updateTimeFromInput()">
                                 </div>
-                                <div class="time-input-group">
+                                 <div class="cutter-zoom-controls">
-                                    <label id="cutterEndLabel" for="endTime">Ende:</label>
+                                     <button type="button" class="cutter-icon-button" id="cutterZoomOutBtn" onclick="changeCutterZoom(-0.25)" disabled aria-label="Verkleinern"><svg aria-hidden="true" viewBox="0 0 24 24"><path d="M5 12h14"></path></svg></button>
-                                    <input type="text" id="endTime" value="00:00:00" onchange="updateTimeFromInput()">
+                                     <input type="range" id="cutterZoom" min="1" max="16" step="0.05" value="1" disabled aria-label="Timeline-Zoom">
+                                     <button type="button" class="cutter-icon-button" id="cutterZoomInBtn" onclick="changeCutterZoom(0.25)" disabled aria-label="Vergrößern"><svg aria-hidden="true" viewBox="0 0 24 24"><path d="M12 5v14M5 12h14"></path></svg></button>
+                                 </div>
+                                 <div class="cutter-actions">
+                                     <button type="button" class="btn-secondary" id="cutterCancelExportBtn" onclick="cancelCutterExport()" hidden>Abbrechen</button>
+                                     <button type="button" class="btn-primary" id="btnCut" onclick="startCutting()" disabled>Video exportieren</button>
+                                 </div>
+                             </div>
+                            <div class="cutter-timeline-scroll" id="cutterTimelineScroll">
+                                <div class="timeline" id="timeline">
+                                    <div class="cutter-ruler" id="cutterRuler"></div>
+                                    <div class="cutter-track cutter-video-track" id="cutterVideoTrack">
+                                        <span class="cutter-track-label" id="cutterVideoTrackLabel">VIDEO</span>
+                                        <div class="cutter-thumbnail-strip" id="cutterThumbnailStrip"></div>
+                                    </div>
+                                    <div class="cutter-track cutter-audio-track" id="cutterAudioTrack">
+                                        <span class="cutter-track-label" id="cutterAudioTrackLabel">AUDIO</span>
+                                        <img id="cutterWaveform" alt="" draggable="false">
+                                        <div class="cutter-audio-empty" id="cutterAudioEmpty">Keine Audiospur</div>
+                                    </div>
+                                    <div class="cutter-outside-shade cutter-outside-left" id="cutterOutsideLeft"></div>
+                                    <div class="cutter-outside-shade cutter-outside-right" id="cutterOutsideRight"></div>
+                                    <div class="timeline-selection" id="timelineSelection">
+                                        <button type="button" class="timeline-handle start" id="cutterTrimStartHandle" aria-label="Start verschieben"></button>
+                                        <button type="button" class="timeline-handle end" id="cutterTrimEndHandle" aria-label="Ende verschieben"></button>
+                                    </div>
+                                    <div class="cutter-cut-overlays" id="cutterCutOverlays"></div>
+                                    <div class="timeline-current" id="timelineCurrent"><span></span></div>
                                 </div>
                             </div>
                         </div>
@@ -495,9 +615,6 @@
                             <div class="progress-text" id="cutProgressText">0%</div>
                         </div>
 
-                        <div class="cutter-actions">
-                            <button type="button" class="btn-primary" id="btnCut" onclick="startCutting()" disabled>Schneiden</button>
-                        </div>
                     </div>
                 </div>
 
@@ -783,7 +900,7 @@
 
                     <div class="settings-card" data-settings-pane="updates" hidden>
                         <h3 id="updateTitle">Updates</h3>
-                        <p id="versionInfo" class="card-intro">Version: v1.0.4</p>
+                        <p id="versionInfo" class="card-intro">Version: v1.0.5</p>
                         <button type="button" class="btn-secondary" id="checkUpdateBtn" onclick="checkUpdate()">Nach Updates suchen</button>
                     </div>
 
@@ -964,6 +1081,7 @@
     <script src="../dist/renderer-profile.js"></script>
     <script src="../dist/renderer-vod-hover.js"></script>
     <script src="../dist/renderer-command-palette.js"></script>
+    <script src="../dist/renderer-cutter.js"></script>
     <script src="../dist/renderer.js"></script>
 </body>
 </html>

src/main.ts

@@ -1,8 +1,9 @@
-import { app, BrowserWindow, ipcMain, dialog, shell, nativeTheme, Notification } from 'electron';
+import { app, BrowserWindow, ipcMain, dialog, shell, nativeTheme, Notification, type IpcMainInvokeEvent } from 'electron';
 import * as path from 'path';
 import * as fs from 'fs';
 import { spawn, ChildProcess, execSync, spawnSync } from 'child_process';
 import { connect as tlsConnect, TLSSocket } from 'node:tls';
+import { pathToFileURL } from 'node:url';
 import axios from 'axios';
 import { autoUpdater } from 'electron-updater';
 import { compareUpdateVersions, isNewerUpdateVersion, normalizeUpdateVersion } from './main/domain/update-version-utils';
@@ -36,6 +37,8 @@ import {
 import { CustomClip, MergeGroupItem, MergeGroup, QueueItem, DownloadProgress, DownloadResult } from './types';
 import { buildVodPreviewFrameUrls } from './main/domain/vod-preview';
 import { getWindowsAppIdentity } from './main/domain/app-identity';
+import { addCutAt, createVideoEditorState, getPlayableSegments, setTrimRange, type EditorCut } from './main/domain/video-editor';
+import { calculateCutterExportProgress, createCutterExportPlan } from './main/domain/cutter-export';
 import {
     setDebugLogFn, initToolDirs,
     getStreamlinkPath, getStreamlinkCommand, getFFmpegPath, getFFprobePath,
@@ -250,6 +253,49 @@ interface VideoInfo {
     width: number;
     height: number;
     fps: number;
+    hasAudio: boolean;
+    videoCodec: string;
+    audioCodec: string | null;
+    previewCompatible: boolean;
+    variableFrameRate: boolean;
+}
+
+interface VideoEditorMedia {
+    sourceUrl: string;
+    info: VideoInfo;
+    jobId: number;
+    thumbnails: string[];
+    waveform: string | null;
+}
+
+interface VideoEditorAssets {
+    jobId: number;
+    thumbnails: string[];
+    thumbnailSprite: string | null;
+    thumbnailCount: number;
+    pixelWidth: number;
+    pixelHeight: number;
+}
+
+interface VideoEditorWaveform {
+    jobId: number;
+    waveform: string | null;
+    pixelWidth: number;
+    pixelHeight: number;
+}
+
+interface VideoEditorAssetProfile {
+    timelineWidth: number;
+    trackHeight: number;
+    pixelRatio: number;
+}
+
+interface VideoEditExportRequest {
+    inputFile: string;
+    outputFile?: string;
+    trimStart: number;
+    trimEnd: number;
+    cuts: EditorCut[];
 }
 
 interface ReleaseUpdateInfo {
@@ -685,6 +731,31 @@ let queuePaused = false;
 // and clip downloads via activeClipProcesses. Keeping these separate
 // prevents cancel-download from killing an unrelated cutter ffmpeg.
 let currentEditorProcess: ChildProcess | null = null;
+let currentCutterProcess: ChildProcess | null = null;
+let currentCutterPartialFile: string | null = null;
+let cutterExportActive = false;
+let cutterExportCancelled = false;
+let cutterPreparedInput: { path: string; size: number; mtimeMs: number; dev: number; ino: number } | null = null;
+let cutterMediaGeneration = 0;
+let cutterMediaRequestGeneration = 0;
+let cutterAssetRunGeneration = 0;
+let cutterWaveformGeneration = 0;
+let cutterMediaJob: {
+    jobId: number;
+    path: string;
+    identity: { path: string; size: number; mtimeMs: number; dev: number; ino: number };
+    info: VideoInfo;
+    waveform: VideoEditorWaveform | null;
+    waveformPromise: Promise<VideoEditorWaveform | null> | null;
+    previewDirectory: string | null;
+} | null = null;
+let appShutdownStarted = false;
+const currentCutterMediaProcesses = new Set<ChildProcess>();
+const currentCutterWaveformProcesses = new Set<ChildProcess>();
+const currentCutterProbeProcesses = new Set<ChildProcess>();
+const currentCutterInfoProcesses = new Set<ChildProcess>();
+const currentCutterExportProcesses = new Set<ChildProcess>();
+const currentCutterPreviewProcesses = new Set<ChildProcess>();
 // Per-item cancellation lives in `cancelledItemIds`. The previous global
 // `currentDownloadCancelled` flag was redundant once pause/cancel/remove
 // started iterating activeDownloads and adding each item to that Set; it
@@ -2677,7 +2748,20 @@ async function getClipInfo(clipId: string): Promise<any | null> {
 // ==========================================
 // VIDEO INFO (for cutter)
 // ==========================================
-async function getVideoInfo(filePath: string): Promise<VideoInfo | null> {
+function isVideoEditorPreviewCompatible(filePath: string, videoCodec: string, audioCodec: string | null): boolean {
+    const extension = path.extname(filePath).toLowerCase();
+    const audioCompatible = !audioCodec || ['aac', 'mp3', 'opus', 'vorbis'].includes(audioCodec);
+    if (['.mp4', '.m4v', '.mov'].includes(extension)) return ['h264', 'av1', 'vp9'].includes(videoCodec) && audioCompatible;
+    if (extension === '.webm') return ['vp8', 'vp9', 'av1'].includes(videoCodec) && audioCompatible;
+    if (extension === '.mkv') return ['h264', 'av1', 'vp8', 'vp9'].includes(videoCodec) && audioCompatible;
+    return false;
+}
+
+function isSupportedVideoEditorInput(filePath: string): boolean {
+    return ['.mp4', '.m4v', '.mov', '.webm', '.mkv', '.ts', '.avi'].includes(path.extname(filePath).toLowerCase());
+}
+
+async function getVideoInfo(filePath: string, trackedProcesses?: Set<ChildProcess>, timeoutMs = 30000): Promise<VideoInfo | null> {
     const ffmpegReady = await ensureFfmpegInstalled();
     if (!ffmpegReady) {
         appendDebugLog('get-video-info-missing-ffmpeg');
@@ -2695,7 +2779,29 @@ async function getVideoInfo(filePath: string): Promise<VideoInfo | null> {
         ];
 
         const proc = spawn(ffprobe, args, { windowsHide: true });
+        trackedProcesses?.add(proc);
+        proc.stderr?.resume();
         let output = '';
+        let resolved = false;
+        let forceResolveTimer: NodeJS.Timeout | null = null;
+
+        const resolveOnce = (value: VideoInfo | null): void => {
+            if (resolved) return;
+            resolved = true;
+            resolve(value);
+        };
+
+        const finish = (value: VideoInfo | null): void => {
+            clearTimeout(timeoutTimer);
+            if (forceResolveTimer) clearTimeout(forceResolveTimer);
+            trackedProcesses?.delete(proc);
+            resolveOnce(value);
+        };
+
+        const timeoutTimer = setTimeout(() => {
+            try { proc.kill(); } catch { }
+            forceResolveTimer = setTimeout(() => resolveOnce(null), 2000);
+        }, timeoutMs);
 
         proc.stdout?.on('data', (data) => {
             output += data.toString();
@@ -2703,29 +2809,447 @@ async function getVideoInfo(filePath: string): Promise<VideoInfo | null> {
 
         proc.on('close', (code) => {
             if (code !== 0) {
-                resolve(null);
+                finish(null);
                 return;
             }
 
             try {
                 const info = JSON.parse(output);
                 const videoStream = info.streams?.find((s: any) => s.codec_type === 'video');
+                const audioStream = info.streams?.find((s: any) => s.codec_type === 'audio');
+                const duration = parseFloat(info.format?.duration || videoStream?.duration || '0');
+                const averageFps = parseFrameRate(videoStream?.avg_frame_rate);
+                const realFps = parseFrameRate(videoStream?.r_frame_rate);
+                const fps = averageFps > 0 ? averageFps : realFps;
 
-                resolve({
+                if (!videoStream || !Number.isFinite(duration) || duration <= 0 || !videoStream.width || !videoStream.height || !Number.isFinite(fps) || fps <= 0) {
-                    duration: parseFloat(info.format?.duration || '0'),
+                    finish(null);
-                    width: videoStream?.width || 0,
+                    return;
-                    height: videoStream?.height || 0,
+                }
-                    fps: parseFrameRate(videoStream?.r_frame_rate)
+
+                const videoCodec = String(videoStream.codec_name || '').toLowerCase();
+                const audioCodec = audioStream ? String(audioStream.codec_name || '').toLowerCase() : null;
+                const variableFrameRate = averageFps > 0 && realFps > 0 && Math.abs(averageFps - realFps) / Math.max(averageFps, realFps) > 0.005;
+                finish({
+                    duration,
+                    width: videoStream.width,
+                    height: videoStream.height,
+                    fps,
+                    hasAudio: Boolean(audioStream),
+                    videoCodec,
+                    audioCodec,
+                    previewCompatible: isVideoEditorPreviewCompatible(filePath, videoCodec, audioCodec),
+                    variableFrameRate,
                 });
             } catch {
-                resolve(null);
+                finish(null);
             }
         });
 
-        proc.on('error', () => resolve(null));
+        proc.on('error', () => finish(null));
     });
 }
 
+function cancelCutterMediaPreparation(): void {
+    cutterAssetRunGeneration += 1;
+    for (const process of currentCutterMediaProcesses) {
+        try { process.kill(); } catch { }
+    }
+}
+
+function cancelCutterMetadataPreparation(): void {
+    for (const process of currentCutterProbeProcesses) {
+        try { process.kill(); } catch { }
+    }
+}
+
+function cancelCutterPreviewPreparation(): void {
+    for (const process of currentCutterPreviewProcesses) {
+        try { process.kill(); } catch { }
+    }
+}
+
+function cancelCutterWaveformPreparation(): void {
+    cutterWaveformGeneration += 1;
+    for (const process of currentCutterWaveformProcesses) {
+        try { process.kill(); } catch { }
+    }
+}
+
+function runEditorMediaProcess(args: string[], runGeneration: number): Promise<boolean> {
+    return new Promise((resolve) => {
+        if (runGeneration !== cutterAssetRunGeneration || appShutdownStarted) {
+            resolve(false);
+            return;
+        }
+        const proc = spawn(getFFmpegPath(), args, { windowsHide: true });
+        currentCutterMediaProcesses.add(proc);
+        proc.stderr?.resume();
+        let settled = false;
+        const finish = (success: boolean): void => {
+            if (settled) return;
+            settled = true;
+            currentCutterMediaProcesses.delete(proc);
+            resolve(success && runGeneration === cutterAssetRunGeneration && !appShutdownStarted);
+        };
+        proc.on('close', (code) => finish(code === 0));
+        proc.on('error', () => finish(false));
+    });
+}
+
+function runEditorWaveformProcess(args: string[], runGeneration: number): Promise<boolean> {
+    return new Promise((resolve) => {
+        if (runGeneration !== cutterWaveformGeneration || appShutdownStarted) {
+            resolve(false);
+            return;
+        }
+        const proc = spawn(getFFmpegPath(), args, { windowsHide: true });
+        currentCutterWaveformProcesses.add(proc);
+        proc.stderr?.resume();
+        let settled = false;
+        const finish = (success: boolean): void => {
+            if (settled) return;
+            settled = true;
+            currentCutterWaveformProcesses.delete(proc);
+            resolve(success && runGeneration === cutterWaveformGeneration && !appShutdownStarted);
+        };
+        proc.on('close', (code) => finish(code === 0));
+        proc.on('error', () => finish(false));
+    });
+}
+
+function runEditorPreviewProcess(args: string[], requestGeneration: number): Promise<boolean> {
+    return new Promise((resolve) => {
+        if (requestGeneration !== cutterMediaRequestGeneration || appShutdownStarted) {
+            resolve(false);
+            return;
+        }
+        const proc = spawn(getFFmpegPath(), args, { windowsHide: true });
+        currentCutterPreviewProcesses.add(proc);
+        proc.stderr?.resume();
+        let settled = false;
+        const finish = (success: boolean): void => {
+            if (settled) return;
+            settled = true;
+            currentCutterPreviewProcesses.delete(proc);
+            resolve(success && requestGeneration === cutterMediaRequestGeneration && !appShutdownStarted);
+        };
+        proc.on('close', (code) => finish(code === 0));
+        proc.on('error', () => finish(false));
+    });
+}
+
+function removeCutterPreviewDirectory(directory: string | null): void {
+    if (!directory) return;
+    try { fs.rmSync(directory, { recursive: true, force: true }); } catch { }
+}
+
+function createVideoEditorPreview(filePath: string, info: VideoInfo, requestGeneration: number): Promise<{ sourceUrl: string; directory: string } | null> {
+    const directory = fs.mkdtempSync(path.join(app.getPath('temp'), `tvm-editor-preview-${process.pid}-`));
+    const previewFile = path.join(directory, 'preview.mp4');
+    const copyVideo = ['h264', 'av1', 'vp9'].includes(info.videoCodec);
+    const copyAudio = !info.audioCodec || ['aac', 'mp3'].includes(info.audioCodec);
+    const args = ['-fflags', '+genpts', '-i', filePath, '-map', '0:v:0', '-map', '0:a:0?'];
+    if (copyVideo) args.push('-c:v', 'copy');
+    else args.push('-c:v', 'libx264', '-preset', 'ultrafast', '-crf', '20', '-pix_fmt', 'yuv420p');
+    if (info.hasAudio) {
+        if (copyAudio) args.push('-c:a', 'copy');
+        else args.push('-c:a', 'aac', '-b:a', '160k');
+    } else {
+        args.push('-an');
+    }
+    args.push('-movflags', '+faststart', '-avoid_negative_ts', 'make_zero', '-y', previewFile);
+    return runEditorPreviewProcess(args, requestGeneration).then((success) => {
+        if (!success || !fs.existsSync(previewFile) || fs.statSync(previewFile).size <= 256) {
+            removeCutterPreviewDirectory(directory);
+            return null;
+        }
+        return { sourceUrl: pathToFileURL(previewFile).href, directory };
+    });
+}
+
+function readImageDataUrl(filePath: string): string | null {
+    if (!fs.existsSync(filePath)) return null;
+    const extension = path.extname(filePath).toLowerCase();
+    const mediaType = extension === '.png' ? 'image/png' : 'image/jpeg';
+    return `data:${mediaType};base64,${fs.readFileSync(filePath).toString('base64')}`;
+}
+
+async function prepareVideoEditorMedia(filePath: string): Promise<VideoEditorMedia | null> {
+    if (appShutdownStarted || typeof filePath !== 'string' || !path.isAbsolute(filePath) || !isSupportedVideoEditorInput(filePath) || !fs.existsSync(filePath) || !fs.statSync(filePath).isFile()) return null;
+    const requestGeneration = ++cutterMediaRequestGeneration;
+    cancelCutterPreviewPreparation();
+    cancelCutterMetadataPreparation();
+    const identityBefore = getCutterInputIdentity(filePath);
+    if (!identityBefore) return null;
+    const info = await getVideoInfo(filePath, currentCutterProbeProcesses);
+    const identityAfter = getCutterInputIdentity(filePath);
+    if (!info || info.variableFrameRate || requestGeneration !== cutterMediaRequestGeneration || !cutterInputIdentitiesMatch(identityBefore, identityAfter) || appShutdownStarted) return null;
+    const preview = info.previewCompatible
+        ? { sourceUrl: pathToFileURL(filePath).href, directory: null }
+        : await createVideoEditorPreview(filePath, info, requestGeneration);
+    if (!preview || requestGeneration !== cutterMediaRequestGeneration || !cutterInputIdentitiesMatch(identityBefore, getCutterInputIdentity(filePath)) || appShutdownStarted) {
+        removeCutterPreviewDirectory(preview?.directory || null);
+        return null;
+    }
+    cancelCutterMediaPreparation();
+    cancelCutterWaveformPreparation();
+    removeCutterPreviewDirectory(cutterMediaJob?.previewDirectory || null);
+    const jobId = ++cutterMediaGeneration;
+    cutterMediaJob = { jobId, path: identityAfter!.path, identity: identityAfter!, info, waveform: null, waveformPromise: null, previewDirectory: preview.directory };
+    return {
+        sourceUrl: preview.sourceUrl,
+        info,
+        jobId,
+        thumbnails: [],
+        waveform: null,
+    };
+}
+
+async function prepareVideoEditorWaveform(filePath: string, jobId: number): Promise<VideoEditorWaveform | null> {
+    const job = cutterMediaJob;
+    if (appShutdownStarted || typeof filePath !== 'string' || !path.isAbsolute(filePath) || !Number.isInteger(jobId) || !job || jobId !== job.jobId || normalizeComparablePath(filePath) !== job.path || !cutterInputIdentitiesMatch(getCutterInputIdentity(filePath), job.identity)) return null;
+    if (!job.info.hasAudio) return { jobId, waveform: null, pixelWidth: 32000, pixelHeight: 240 };
+    if (job.waveform) return job.waveform;
+    if (job.waveformPromise) return await job.waveformPromise;
+    const runGeneration = cutterWaveformGeneration;
+    const promise = (async (): Promise<VideoEditorWaveform | null> => {
+        const tempDir = fs.mkdtempSync(path.join(app.getPath('temp'), `tvm-editor-waveform-${process.pid}-`));
+        const waveformFile = path.join(tempDir, 'waveform.png');
+        try {
+            const success = await runEditorWaveformProcess([
+                '-i', filePath,
+                '-filter_complex', 'aformat=channel_layouts=mono,showwavespic=s=32000x240:colors=white',
+                '-frames:v', '1',
+                '-y', waveformFile,
+            ], runGeneration);
+            if (!success || runGeneration !== cutterWaveformGeneration || cutterMediaJob !== job || !cutterInputIdentitiesMatch(getCutterInputIdentity(filePath), job.identity) || appShutdownStarted) return null;
+            const waveform = readImageDataUrl(waveformFile);
+            if (!waveform) return null;
+            const result = { jobId, waveform, pixelWidth: 32000, pixelHeight: 240 };
+            job.waveform = result;
+            return result;
+        } finally {
+            fs.rmSync(tempDir, { recursive: true, force: true });
+        }
+    })();
+    job.waveformPromise = promise;
+    const result = await promise;
+    if (cutterMediaJob === job && job.waveformPromise === promise) job.waveformPromise = null;
+    return result;
+}
+
+async function prepareVideoEditorAssets(filePath: string, jobId: number, profile: VideoEditorAssetProfile): Promise<VideoEditorAssets | null> {
+    if (appShutdownStarted || typeof filePath !== 'string' || !path.isAbsolute(filePath) || !Number.isInteger(jobId) || !profile || !Number.isFinite(profile.timelineWidth) || profile.timelineWidth <= 0 || !Number.isFinite(profile.trackHeight) || profile.trackHeight <= 0 || !Number.isFinite(profile.pixelRatio) || profile.pixelRatio <= 0 || !cutterMediaJob || jobId !== cutterMediaJob.jobId || normalizeComparablePath(filePath) !== cutterMediaJob.path || !cutterInputIdentitiesMatch(getCutterInputIdentity(filePath), cutterMediaJob.identity)) return null;
+    cancelCutterMediaPreparation();
+    const runGeneration = cutterAssetRunGeneration;
+    const info = cutterMediaJob.info;
+    const tempDir = fs.mkdtempSync(path.join(app.getPath('temp'), `tvm-editor-media-${process.pid}-`));
+    const pixelRatio = Math.min(3, Math.max(1, profile.pixelRatio));
+    const pixelWidth = info.duration <= 120 ? 32000 : Math.round(Math.min(32000, Math.max(1800, Math.ceil(profile.timelineWidth * pixelRatio))));
+    const thumbnailCount = info.duration <= 120 ? 200 : Math.round(Math.min(100, Math.max(30, Math.ceil(pixelWidth / 320))));
+    const thumbnailTileWidth = Math.max(428, Math.ceil(pixelWidth / thumbnailCount / 2) * 2);
+    const thumbnailTileHeight = 240;
+    try {
+        const thumbnailsReady = await runEditorMediaProcess([
+            '-i', filePath,
+            '-vf', `fps=${thumbnailCount / info.duration},scale=${thumbnailTileWidth}:${thumbnailTileHeight}:force_original_aspect_ratio=increase:flags=lanczos,crop=${thumbnailTileWidth}:${thumbnailTileHeight}`,
+            '-frames:v', String(thumbnailCount),
+            '-q:v', '2',
+            '-start_number', '1',
+            '-y', path.join(tempDir, 'thumb-%03d.jpg'),
+        ], runGeneration);
+        if (runGeneration !== cutterAssetRunGeneration || !cutterMediaJob || jobId !== cutterMediaJob.jobId || !cutterInputIdentitiesMatch(getCutterInputIdentity(filePath), cutterMediaJob.identity) || appShutdownStarted) return null;
+        if (!thumbnailsReady) return null;
+        const thumbnails = fs.readdirSync(tempDir)
+            .filter((name) => /^thumb-\d+\.jpg$/i.test(name))
+            .sort()
+            .map((name) => readImageDataUrl(path.join(tempDir, name)))
+            .filter((value): value is string => Boolean(value));
+        if (thumbnails.length < Math.floor(thumbnailCount * 0.95)) return null;
+        return {
+            jobId,
+            thumbnails,
+            thumbnailSprite: null,
+            thumbnailCount: thumbnails.length,
+            pixelWidth,
+            pixelHeight: thumbnailTileHeight,
+        };
+    } finally {
+        fs.rmSync(tempDir, { recursive: true, force: true });
+    }
+}
+
+function getCutterInputIdentity(filePath: string): { path: string; size: number; mtimeMs: number; dev: number; ino: number } | null {
+    try {
+        const stat = fs.statSync(filePath);
+        if (!stat.isFile()) return null;
+        return { path: normalizeComparablePath(filePath), size: stat.size, mtimeMs: stat.mtimeMs, dev: stat.dev, ino: stat.ino };
+    } catch {
+        return null;
+    }
+}
+
+function cutterInputIdentityMatches(filePath: string): boolean {
+    const current = getCutterInputIdentity(filePath);
+    return cutterInputIdentitiesMatch(current, cutterPreparedInput);
+}
+
+function cutterInputIdentitiesMatch(
+    left: { path: string; size: number; mtimeMs: number; dev: number; ino: number } | null,
+    right: { path: string; size: number; mtimeMs: number; dev: number; ino: number } | null,
+): boolean {
+    return Boolean(left && right
+        && left.path === right.path
+        && left.size === right.size
+        && left.mtimeMs === right.mtimeMs
+        && left.dev === right.dev
+        && left.ino === right.ino);
+}
+
+function normalizeComparablePath(filePath: string): string {
+    const resolved = path.resolve(filePath);
+    let canonical = resolved;
+    try { canonical = fs.realpathSync.native(resolved); } catch {
+        try {
+            const parent = fs.realpathSync.native(path.dirname(resolved));
+            canonical = path.join(parent, path.basename(resolved));
+        } catch { }
+    }
+    return process.platform === 'win32' ? canonical.toLocaleLowerCase('en-US') : canonical;
+}
+
+function pathsReferToSameFile(left: string, right: string): boolean {
+    if (normalizeComparablePath(left) === normalizeComparablePath(right)) return true;
+    if (!fs.existsSync(left) || !fs.existsSync(right)) return false;
+    try {
+        const leftStat = fs.statSync(left);
+        const rightStat = fs.statSync(right);
+        return leftStat.dev === rightStat.dev && leftStat.ino !== 0 && leftStat.ino === rightStat.ino;
+    } catch {
+        return false;
+    }
+}
+
+function publishVideoEditorOutput(partialFile: string, outputFile: string): void {
+    const backupFile = `${outputFile}.${process.pid}.${Date.now()}.tvm-backup`;
+    const hadExistingOutput = fs.existsSync(outputFile);
+    if (hadExistingOutput) fs.renameSync(outputFile, backupFile);
+    try {
+        fs.renameSync(partialFile, outputFile);
+        if (hadExistingOutput) {
+            try { fs.rmSync(backupFile, { force: true }); } catch { }
+        }
+    } catch (error) {
+        if (hadExistingOutput && fs.existsSync(backupFile) && !fs.existsSync(outputFile)) fs.renameSync(backupFile, outputFile);
+        throw error;
+    }
+}
+
+async function performVideoEditExport(request: VideoEditExportRequest, onProgress: (percent: number) => void): Promise<boolean> {
+    if (appShutdownStarted) return false;
+    if (!request || typeof request.inputFile !== 'string' || typeof request.outputFile !== 'string') return false;
+    if (!path.isAbsolute(request.inputFile) || !path.isAbsolute(request.outputFile) || !fs.existsSync(request.inputFile)) return false;
+    if (path.extname(request.outputFile).toLowerCase() !== '.mp4' || pathsReferToSameFile(request.inputFile, request.outputFile)) return false;
+    if (!Number.isFinite(request.trimStart) || !Number.isFinite(request.trimEnd) || !Array.isArray(request.cuts) || request.cuts.length > 64) return false;
+    if (request.cuts.some((cut) => !isPlainObject(cut) || typeof cut.id !== 'string' || !Number.isFinite(cut.start) || !Number.isFinite(cut.end))) return false;
+    const inputIdentity = getCutterInputIdentity(request.inputFile);
+    if (!cutterInputIdentitiesMatch(inputIdentity, cutterPreparedInput)) return false;
+    const info = await getVideoInfo(request.inputFile, currentCutterExportProcesses);
+    if (!info || cutterExportCancelled) return false;
+    let state = setTrimRange(createVideoEditorState(info.duration, info.fps), request.trimStart, request.trimEnd);
+    if (Math.abs(state.trimStart - request.trimStart) > 1 / info.fps || Math.abs(state.trimEnd - request.trimEnd) > 1 / info.fps) return false;
+    try {
+        for (const cut of request.cuts) {
+            state = addCutAt(state, cut.start, cut.end - cut.start).state;
+        }
+    } catch {
+        return false;
+    }
+    const segments = getPlayableSegments(state);
+    if (segments.length === 0) return false;
+    const outputDir = path.dirname(request.outputFile);
+    if (!fs.existsSync(outputDir) || !fs.statSync(outputDir).isDirectory()) return false;
+    const inputBytes = fs.statSync(request.inputFile).size;
+    const diskCheck = ensureDiskSpace(outputDir, Math.max(128 * 1024 * 1024, Math.ceil(inputBytes * 1.25)), 'Video-Editor');
+    if (!diskCheck.success) return false;
+    const partialFile = path.join(outputDir, `.${path.basename(request.outputFile, '.mp4')}.${process.pid}.${Date.now()}.tvm-edit.mp4`);
+    const plan = createCutterExportPlan({ inputFile: request.inputFile, outputFile: partialFile, segments, hasAudio: info.hasAudio });
+    if (plan.filterComplex.length > 24000 || cutterExportCancelled) return false;
+    currentCutterPartialFile = partialFile;
+    const success = await new Promise<boolean>((resolve) => {
+        const proc = spawn(getFFmpegPath(), plan.ffmpegArgs, { windowsHide: true });
+        currentCutterProcess = proc;
+        currentCutterExportProcesses.add(proc);
+        proc.stderr?.resume();
+        let stdout = '';
+        proc.stdout?.on('data', (data) => {
+            stdout += data.toString();
+            const lines = stdout.split(/\r?\n/);
+            stdout = lines.pop() || '';
+            for (const line of lines) {
+                const match = line.match(/^out_time_(?:us|ms)=(\d+)$/);
+                if (match) onProgress(calculateCutterExportProgress(Number(match[1]) / 1_000_000, plan));
+            }
+        });
+        proc.on('close', (code) => {
+            currentCutterExportProcesses.delete(proc);
+            if (currentCutterProcess === proc) currentCutterProcess = null;
+            resolve(code === 0 && !cutterExportCancelled);
+        });
+        proc.on('error', () => {
+            currentCutterExportProcesses.delete(proc);
+            if (currentCutterProcess === proc) currentCutterProcess = null;
+            resolve(false);
+        });
+    });
+    if (!success || !fs.existsSync(partialFile) || fs.statSync(partialFile).size <= 256) {
+        fs.rmSync(partialFile, { force: true });
+        currentCutterPartialFile = null;
+        return false;
+    }
+    if (cutterExportCancelled) {
+        fs.rmSync(partialFile, { force: true });
+        currentCutterPartialFile = null;
+        return false;
+    }
+    const outputInfo = await getVideoInfo(partialFile, currentCutterExportProcesses);
+    if (cutterExportCancelled || !outputInfo || Math.abs(outputInfo.duration - plan.remainingDuration) > Math.max(0.12, 3 / info.fps)) {
+        fs.rmSync(partialFile, { force: true });
+        currentCutterPartialFile = null;
+        return false;
+    }
+    if (cutterExportCancelled || pathsReferToSameFile(request.inputFile, request.outputFile) || !cutterInputIdentitiesMatch(getCutterInputIdentity(request.inputFile), inputIdentity)) {
+        fs.rmSync(partialFile, { force: true });
+        currentCutterPartialFile = null;
+        return false;
+    }
+    publishVideoEditorOutput(partialFile, request.outputFile);
+    currentCutterPartialFile = null;
+    onProgress(100);
+    return true;
+}
+
+async function exportVideoEdit(request: VideoEditExportRequest, onProgress: (percent: number) => void): Promise<{ success: boolean; cancelled: boolean }> {
+    if (cutterExportActive || appShutdownStarted) return { success: false, cancelled: false };
+    cutterExportActive = true;
+    cutterExportCancelled = false;
+    try {
+        const success = await performVideoEditExport(request, onProgress);
+        return { success, cancelled: !success && cutterExportCancelled };
+    } catch (error) {
+        appendDebugLog('video-editor-export-failed', String(error));
+        return { success: false, cancelled: cutterExportCancelled };
+    } finally {
+        cutterExportActive = false;
+        cutterExportCancelled = false;
+        if (currentCutterPartialFile && !currentCutterProcess) {
+            try { fs.rmSync(currentCutterPartialFile, { force: true }); } catch { }
+            currentCutterPartialFile = null;
+        }
+    }
+}
+
 // ==========================================
 // VIDEO CUTTER
 // ==========================================
@@ -2750,6 +3274,7 @@ async function extractFrame(filePath: string, timeSeconds: number): Promise<stri
         ];
 
         const proc = spawn(ffmpeg, args, { windowsHide: true });
+        proc.stderr?.resume();
 
         proc.on('close', (code) => {
             if (code === 0 && fs.existsSync(tempFile)) {
@@ -6190,7 +6715,13 @@ function createWindow(): void {
         mainWindow.removeMenu();
     }
 
-    mainWindow.loadFile(path.join(__dirname, '../src/index.html'));
+    const rendererFile = path.join(__dirname, '../src/index.html');
+    const rendererUrl = pathToFileURL(rendererFile).href;
+    mainWindow.webContents.on('will-navigate', (event, url) => {
+        if (url.split(/[?#]/, 1)[0] !== rendererUrl) event.preventDefault();
+    });
+    mainWindow.webContents.setWindowOpenHandler(() => ({ action: 'deny' }));
+    mainWindow.loadFile(rendererFile);
 
     mainWindow.webContents.on('did-finish-load', () => {
         emitQueueUpdated(true);
@@ -6971,7 +7502,7 @@ ipcMain.handle('select-video-file', async () => {
     const result = await dialog.showOpenDialog(mainWindow!, {
         properties: ['openFile'],
         filters: [
-            { name: 'Video Files', extensions: ['mp4', 'mkv', 'ts', 'mov', 'avi'] }
+            { name: 'Video Files', extensions: ['mp4', 'm4v', 'mov', 'webm', 'mkv', 'ts', 'avi'] }
         ]
     });
     return result.filePaths[0] || null;
@@ -7433,15 +7964,85 @@ ipcMain.handle('import-config', async () => {
     }
 });
 
+function isTrustedRendererEvent(event: IpcMainInvokeEvent): boolean {
+    if (!mainWindow || event.sender.id !== mainWindow.webContents.id) return false;
+    const rendererUrl = pathToFileURL(path.join(__dirname, '../src/index.html')).href;
+    const senderUrl = event.senderFrame?.url || event.sender.getURL();
+    return senderUrl.split(/[?#]/, 1)[0] === rendererUrl;
+}
+
+function isPathInsideDirectory(rootDirectory: string, candidate: string): boolean {
+    const root = normalizeComparablePath(rootDirectory);
+    const target = normalizeComparablePath(candidate);
+    const relative = path.relative(root, target);
+    return relative !== '' && !relative.startsWith('..') && !path.isAbsolute(relative);
+}
+
 // Video Cutter IPC
-ipcMain.handle('get-video-info', async (_, filePath: string) => {
+ipcMain.handle('get-video-info', async (event, filePath: string) => {
-    return await getVideoInfo(filePath);
+    if (!isTrustedRendererEvent(event) || appShutdownStarted) return null;
+    return await getVideoInfo(filePath, currentCutterInfoProcesses);
 });
 
-ipcMain.handle('extract-frame', async (_, filePath: string, timeSeconds: number) => {
+ipcMain.handle('extract-frame', async (event, filePath: string, timeSeconds: number) => {
+    if (!isTrustedRendererEvent(event) || appShutdownStarted) return null;
     return await extractFrame(filePath, timeSeconds);
 });
 
+ipcMain.handle('prepare-video-editor-media', async (event, filePath: string) => {
+    if (!isTrustedRendererEvent(event) || appShutdownStarted) return null;
+    const media = await prepareVideoEditorMedia(filePath);
+    if (media && cutterMediaJob?.jobId === media.jobId) cutterPreparedInput = cutterMediaJob.identity;
+    return media;
+});
+
+ipcMain.handle('prepare-video-editor-waveform', async (event, filePath: string, jobId: number) => {
+    if (!isTrustedRendererEvent(event) || appShutdownStarted) return null;
+    return await prepareVideoEditorWaveform(filePath, jobId);
+});
+
+ipcMain.handle('prepare-video-editor-assets', async (event, filePath: string, jobId: number, profile: VideoEditorAssetProfile) => {
+    if (!isTrustedRendererEvent(event) || appShutdownStarted) return null;
+    return await prepareVideoEditorAssets(filePath, jobId, profile);
+});
+
+ipcMain.handle('cancel-video-editor-assets', (event, jobId: number) => {
+    if (!isTrustedRendererEvent(event) || !Number.isInteger(jobId) || cutterMediaJob?.jobId !== jobId) return false;
+    cancelCutterMediaPreparation();
+    return true;
+});
+
+ipcMain.handle('export-video-edit', async (event, request: VideoEditExportRequest) => {
+    if (!isTrustedRendererEvent(event) || appShutdownStarted || !request || typeof request.inputFile !== 'string') return { success: false, outputFile: null };
+    if (!cutterInputIdentityMatches(request.inputFile)) return { success: false, outputFile: null };
+    let outputFile: string | null = null;
+    const testRoot = process.env.TWITCH_VOD_MANAGER_E2E_CUTTER_OUTPUT_ROOT;
+    if (testRoot && typeof request.outputFile === 'string' && isPathInsideDirectory(testRoot, request.outputFile)) {
+        outputFile = request.outputFile;
+    } else {
+        const defaultName = path.join(path.dirname(request.inputFile), `${path.basename(request.inputFile, path.extname(request.inputFile))}_edited.mp4`);
+        const result = await dialog.showSaveDialog(mainWindow!, {
+            defaultPath: defaultName,
+            filters: [{ name: 'MP4 Video', extensions: ['mp4'] }],
+        });
+        if (result.canceled || !result.filePath) return { success: false, outputFile: null, cancelled: true };
+        outputFile = result.filePath;
+    }
+    const outcome = await exportVideoEdit({ ...request, outputFile }, (percent) => {
+        mainWindow?.webContents.send('cut-progress', percent);
+    });
+    return { success: outcome.success, outputFile: outcome.success ? outputFile : null, cancelled: outcome.cancelled || undefined };
+});
+
+ipcMain.handle('cancel-video-edit', (event) => {
+    if (!isTrustedRendererEvent(event) || !cutterExportActive) return false;
+    cutterExportCancelled = true;
+    for (const process of currentCutterExportProcesses) {
+        try { process.kill(); } catch { }
+    }
+    return true;
+});
+
 ipcMain.handle('cut-video', async (_, inputFile: string, startTime: number, endTime: number) => {
     const dir = path.dirname(inputFile);
     const baseName = path.basename(inputFile, path.extname(inputFile));
@@ -7495,11 +8096,40 @@ ipcMain.handle('save-video-dialog', async (_, defaultName: string) => {
 let appDb: DbHandle | null = null;
 export function getAppDb(): DbHandle | null { return appDb; }
 
+function cleanupStaleCutterMediaDirectories(): number {
+    const tempRoot = path.resolve(app.getPath('temp'));
+    let removed = 0;
+    try {
+        for (const name of fs.readdirSync(tempRoot)) {
+            if (!/^tvm-editor-(?:media|waveform|preview)-[A-Za-z0-9_-]+$/.test(name)) continue;
+            const candidate = path.resolve(tempRoot, name);
+            if (path.dirname(candidate) !== tempRoot) continue;
+            const processMatch = name.match(/^tvm-editor-(?:media|waveform|preview)-(\d+)-/);
+            if (processMatch) {
+                const ownerPid = Number(processMatch[1]);
+                if (ownerPid === process.pid) continue;
+                try {
+                    process.kill(ownerPid, 0);
+                    continue;
+                } catch { }
+            } else {
+                const ageMs = Date.now() - fs.statSync(candidate).mtimeMs;
+                if (ageMs < 24 * 60 * 60 * 1000) continue;
+            }
+            fs.rmSync(candidate, { recursive: true, force: true });
+            removed += 1;
+        }
+    } catch { }
+    return removed;
+}
+
 app.whenReady().then(() => {
     const removedPartialDownloads = partialDownloadRegistry.cleanup();
     if (removedPartialDownloads.length > 0) {
         appendDebugLog('partial-downloads-cleaned-on-startup', { count: removedPartialDownloads.length });
     }
+    const removedCutterMediaDirectories = cleanupStaleCutterMediaDirectories();
+    if (removedCutterMediaDirectories > 0) appendDebugLog('cutter-media-cleaned-on-startup', { count: removedCutterMediaDirectories });
     refreshBundledToolPaths(true);
     startMetadataCacheCleanup();
     startDebugLogFlushTimer();
@@ -7544,9 +8174,26 @@ let shutdownCleanupDone = false;
 let quitAfterCleanup = false;
 let shutdownPromise: Promise<void> | null = null;
 
+function waitForChildProcessClose(process: ChildProcess | null, timeoutMs = 5000): Promise<void> {
+    if (!process || process.exitCode !== null || process.signalCode !== null) return Promise.resolve();
+    return new Promise((resolve) => {
+        let settled = false;
+        const finish = (): void => {
+            if (settled) return;
+            settled = true;
+            clearTimeout(timer);
+            resolve();
+        };
+        const timer = setTimeout(finish, timeoutMs);
+        process.once('close', finish);
+        process.once('error', finish);
+    });
+}
+
 async function shutdownCleanup(reason: 'window-all-closed' | 'before-quit'): Promise<void> {
     if (shutdownCleanupDone) return;
     shutdownCleanupDone = true;
+    appShutdownStarted = true;
 
     appendDebugLog('shutdown-cleanup', { reason });
 
@@ -7579,10 +8226,34 @@ async function shutdownCleanup(reason: 'window-all-closed' | 'before-quit'): Pro
     activeClipProcesses.clear();
 
     if (currentEditorProcess) {
-        try { currentEditorProcess.kill(); } catch { /* already exited */ }
+        const editorProcess = currentEditorProcess;
+        try { editorProcess.kill(); } catch { /* already exited */ }
+        await waitForChildProcessClose(editorProcess);
         currentEditorProcess = null;
     }
 
+    if (cutterExportActive) cutterExportCancelled = true;
+    const exportProcesses = [...currentCutterExportProcesses];
+    for (const process of exportProcesses) {
+        try { process.kill(); } catch { }
+    }
+    await Promise.all(exportProcesses.map((process) => waitForChildProcessClose(process)));
+    if (currentCutterProcess && exportProcesses.includes(currentCutterProcess)) currentCutterProcess = null;
+    const mediaProcesses = [...currentCutterMediaProcesses, ...currentCutterWaveformProcesses, ...currentCutterProbeProcesses, ...currentCutterInfoProcesses, ...currentCutterPreviewProcesses];
+    cancelCutterMediaPreparation();
+    cancelCutterWaveformPreparation();
+    cancelCutterMetadataPreparation();
+    cancelCutterPreviewPreparation();
+    for (const process of currentCutterInfoProcesses) {
+        try { process.kill(); } catch { }
+    }
+    await Promise.all(mediaProcesses.map((process) => waitForChildProcessClose(process)));
+    removeCutterPreviewDirectory(cutterMediaJob?.previewDirectory || null);
+    if (currentCutterPartialFile) {
+        try { fs.rmSync(currentCutterPartialFile, { force: true }); } catch { }
+        currentCutterPartialFile = null;
+    }
+
     saveConfig(config);
     flushQueueSave();
 

src/main/dev-executable.test.ts

@@ -25,7 +25,7 @@ describe.runIf(process.platform === 'win32')('prepareWindowsDevExecutable', () =
             sourcePath,
             destinationPath,
             iconPath,
-            version: '1.0.4'
+            version: '1.0.5'
         });
 
         const executable = ResEdit.NtExecutable.from(fs.readFileSync(destinationPath));

src/main/domain/cutter-export.test.ts

@@ -0,0 +1,116 @@
+import { describe, expect, test } from 'vitest';
+import { calculateCutterExportProgress, createCutterExportPlan } from './cutter-export';
+
+describe('cutter export segments', () => {
+    test('sorts playable segments and preserves the caller input', () => {
+        const segments = [
+            { start: 30, end: 45 },
+            { start: 5, end: 20 },
+        ];
+
+        const plan = createCutterExportPlan({
+            inputFile: 'D:\\media\\source.mp4',
+            outputFile: 'D:\\media\\result.mp4',
+            segments,
+            hasAudio: true,
+        });
+
+        expect(plan.segments).toEqual([
+            { start: 5, end: 20 },
+            { start: 30, end: 45 },
+        ]);
+        expect(plan.remainingDuration).toBe(30);
+        expect(segments).toEqual([
+            { start: 30, end: 45 },
+            { start: 5, end: 20 },
+        ]);
+    });
+
+    test('builds an audio and video concat filter with a separated argument list', () => {
+        const plan = createCutterExportPlan({
+            inputFile: 'D:\\media folder\\source.mp4',
+            outputFile: 'D:\\exports\\result.mp4',
+            segments: [
+                { start: 5, end: 20 },
+                { start: 30.5, end: 45.25 },
+            ],
+            hasAudio: true,
+        });
+
+        expect(plan.filterComplex).toBe('[0:v]trim=start=5:end=20,setpts=PTS-STARTPTS[v0];[0:a]atrim=start=5:end=20,asetpts=PTS-STARTPTS[a0];[0:v]trim=start=30.5:end=45.25,setpts=PTS-STARTPTS[v1];[0:a]atrim=start=30.5:end=45.25,asetpts=PTS-STARTPTS[a1];[v0][a0][v1][a1]concat=n=2:v=1:a=1[outv][outa]');
+        expect(plan.ffmpegArgs).toEqual([
+            '-i', 'D:\\media folder\\source.mp4',
+            '-filter_complex', plan.filterComplex,
+            '-map', '[outv]',
+            '-map', '[outa]',
+            '-c:v', 'libx264',
+            '-preset', 'veryfast',
+            '-crf', '20',
+            '-pix_fmt', 'yuv420p',
+            '-c:a', 'aac',
+            '-b:a', '160k',
+            '-movflags', '+faststart',
+            '-progress', 'pipe:1',
+            '-y', 'D:\\exports\\result.mp4',
+        ]);
+    });
+
+    test('builds a video-only concat filter without audio mappings or codecs', () => {
+        const plan = createCutterExportPlan({
+            inputFile: 'input.mkv',
+            outputFile: 'output.mp4',
+            segments: [
+                { start: 0, end: 10 },
+                { start: 12, end: 18 },
+            ],
+            hasAudio: false,
+        });
+
+        expect(plan.filterComplex).toBe('[0:v]trim=start=0:end=10,setpts=PTS-STARTPTS[v0];[0:v]trim=start=12:end=18,setpts=PTS-STARTPTS[v1];[v0][v1]concat=n=2:v=1:a=0[outv]');
+        expect(plan.ffmpegArgs).toEqual([
+            '-i', 'input.mkv',
+            '-filter_complex', plan.filterComplex,
+            '-map', '[outv]',
+            '-c:v', 'libx264',
+            '-preset', 'veryfast',
+            '-crf', '20',
+            '-pix_fmt', 'yuv420p',
+            '-an',
+            '-movflags', '+faststart',
+            '-progress', 'pipe:1',
+            '-y', 'output.mp4',
+        ]);
+    });
+
+    test.each([
+        { name: 'empty segment list', segments: [] },
+        { name: 'negative start', segments: [{ start: -1, end: 2 }] },
+        { name: 'zero duration', segments: [{ start: 2, end: 2 }] },
+        { name: 'reversed range', segments: [{ start: 3, end: 2 }] },
+        { name: 'non-finite start', segments: [{ start: Number.NaN, end: 2 }] },
+        { name: 'non-finite end', segments: [{ start: 1, end: Number.POSITIVE_INFINITY }] },
+        { name: 'range below export precision', segments: [{ start: 1, end: 1.0000000001 }] },
+        { name: 'overlap after sorting', segments: [{ start: 10, end: 20 }, { start: 5, end: 12 }] },
+    ])('rejects $name', ({ segments }) => {
+        expect(() => createCutterExportPlan({
+            inputFile: 'input.mp4',
+            outputFile: 'output.mp4',
+            segments,
+            hasAudio: true,
+        })).toThrow();
+    });
+
+    test('calculates progress against the remaining segment duration and clamps it', () => {
+        const plan = createCutterExportPlan({
+            inputFile: 'input.mp4',
+            outputFile: 'output.mp4',
+            segments: [{ start: 10, end: 20 }, { start: 50, end: 70 }],
+            hasAudio: true,
+        });
+
+        expect(calculateCutterExportProgress(0, plan)).toBe(0);
+        expect(calculateCutterExportProgress(15, plan)).toBe(50);
+        expect(calculateCutterExportProgress(45, plan)).toBe(100);
+        expect(calculateCutterExportProgress(-5, plan)).toBe(0);
+    });
+});

src/main/domain/cutter-export.ts

@@ -0,0 +1,109 @@
+import type { EditorSegment } from './video-editor';
+
+export interface CutterExportPlanOptions {
+    inputFile: string;
+    outputFile: string;
+    segments: readonly EditorSegment[];
+    hasAudio: boolean;
+}
+
+export interface CutterExportPlan {
+    segments: EditorSegment[];
+    remainingDuration: number;
+    filterComplex: string;
+    ffmpegArgs: string[];
+}
+
+const precision = 9;
+
+function round(value: number): number {
+    return Number(value.toFixed(precision));
+}
+
+function formatSeconds(value: number): string {
+    return value.toFixed(precision).replace(/\.?0+$/, '');
+}
+
+function validatePath(value: string, name: string): string {
+    if (!value.trim()) throw new Error(`${name} must not be empty`);
+    return value;
+}
+
+function normalizeSegments(segments: readonly EditorSegment[]): EditorSegment[] {
+    if (segments.length === 0) throw new Error('At least one playable segment is required');
+    const normalized = segments.map((segment) => {
+        if (!Number.isFinite(segment.start) || !Number.isFinite(segment.end)) {
+            throw new Error('Segment boundaries must be finite');
+        }
+        if (segment.start < 0 || segment.end <= segment.start) {
+            throw new Error('Segment boundaries must be ordered and non-negative');
+        }
+        const start = round(segment.start);
+        const end = round(segment.end);
+        if (end <= start) throw new Error('Segment duration is below export precision');
+        return { start, end };
+    }).sort((left, right) => left.start - right.start || left.end - right.end);
+
+    for (let index = 1; index < normalized.length; index += 1) {
+        if (normalized[index].start < normalized[index - 1].end) {
+            throw new Error('Playable segments must not overlap');
+        }
+    }
+
+    return normalized;
+}
+
+function createFilterComplex(segments: readonly EditorSegment[], hasAudio: boolean): string {
+    const filters: string[] = [];
+    const concatInputs: string[] = [];
+
+    segments.forEach((segment, index) => {
+        const start = formatSeconds(segment.start);
+        const end = formatSeconds(segment.end);
+        filters.push(`[0:v]trim=start=${start}:end=${end},setpts=PTS-STARTPTS[v${index}]`);
+        concatInputs.push(`[v${index}]`);
+        if (hasAudio) {
+            filters.push(`[0:a]atrim=start=${start}:end=${end},asetpts=PTS-STARTPTS[a${index}]`);
+            concatInputs.push(`[a${index}]`);
+        }
+    });
+
+    filters.push(`${concatInputs.join('')}concat=n=${segments.length}:v=1:a=${hasAudio ? 1 : 0}[outv]${hasAudio ? '[outa]' : ''}`);
+    return filters.join(';');
+}
+
+function createFfmpegArgs(inputFile: string, outputFile: string, filterComplex: string, hasAudio: boolean): string[] {
+    const args = [
+        '-i', inputFile,
+        '-filter_complex', filterComplex,
+        '-map', '[outv]',
+    ];
+    if (hasAudio) args.push('-map', '[outa]');
+    args.push('-c:v', 'libx264', '-preset', 'veryfast', '-crf', '20', '-pix_fmt', 'yuv420p');
+    if (hasAudio) args.push('-c:a', 'aac', '-b:a', '160k');
+    else args.push('-an');
+    args.push('-movflags', '+faststart', '-progress', 'pipe:1', '-y', outputFile);
+    return args;
+}
+
+export function createCutterExportPlan(options: CutterExportPlanOptions): CutterExportPlan {
+    const inputFile = validatePath(options.inputFile, 'inputFile');
+    const outputFile = validatePath(options.outputFile, 'outputFile');
+    const segments = normalizeSegments(options.segments);
+    const remainingDuration = round(segments.reduce((total, segment) => total + segment.end - segment.start, 0));
+    const filterComplex = createFilterComplex(segments, options.hasAudio);
+    return {
+        segments,
+        remainingDuration,
+        filterComplex,
+        ffmpegArgs: createFfmpegArgs(inputFile, outputFile, filterComplex, options.hasAudio),
+    };
+}
+
+export function calculateCutterExportProgress(processedSeconds: number, plan: Pick<CutterExportPlan, 'remainingDuration'>): number {
+    if (!Number.isFinite(processedSeconds) || processedSeconds <= 0) return 0;
+    if (!Number.isFinite(plan.remainingDuration) || plan.remainingDuration <= 0) {
+        throw new Error('remainingDuration must be greater than zero');
+    }
+    return Math.min(100, round(processedSeconds / plan.remainingDuration * 100));
+}

src/main/domain/video-editor.test.ts

@@ -0,0 +1,147 @@
+import { describe, expect, test } from 'vitest';
+import {
+    addCutAt,
+    commitEditorState,
+    createEditorHistory,
+    createVideoEditorState,
+    formatEditorTimecode,
+    getPlayableSegments,
+    movePreviewTimeOutOfCuts,
+    parseEditorTimecode,
+    redoEditorState,
+    setCutRange,
+    setTrimRange,
+    timeToTimelinePercent,
+    timelinePercentToTime,
+    undoEditorState,
+} from './video-editor';
+
+describe('video editor timecodes', () => {
+    test('formats minute and hour timecodes with a frame field', () => {
+        expect(formatEditorTimecode(66.52, 25)).toBe('01:06:13');
+        expect(formatEditorTimecode(3666.52, 25)).toBe('01:01:06:13');
+    });
+
+    test('parses minute and hour timecodes and snaps to a real frame', () => {
+        expect(parseEditorTimecode('01:06:13', 25)).toBeCloseTo(66.52, 8);
+        expect(parseEditorTimecode('01:01:06:13', 25)).toBeCloseTo(3666.52, 8);
+        expect(parseEditorTimecode('00:02:29', 30)).toBeCloseTo(2.9666666667, 8);
+    });
+});
+
+describe('video editor ranges', () => {
+    test('keeps global trim boundaries frame-aligned and ordered', () => {
+        const state = setTrimRange(createVideoEditorState(120, 25), 10.019, 90.021);
+        expect(state.trimStart).toBe(10);
+        expect(state.trimEnd).toBe(90.04);
+    });
+
+    test('adds multiple cuts in timeline order without allowing overlaps', () => {
+        const first = addCutAt(createVideoEditorState(120, 25), 40, 8);
+        const second = addCutAt(first.state, 12, 5);
+        expect(second.state.cuts.map((cut) => [cut.start, cut.end])).toEqual([[12, 17], [40, 48]]);
+
+        const rejected = setCutRange(second.state, first.cut.id, 15, 44);
+        expect(rejected).toEqual(second.state);
+    });
+
+    test('removes cut ranges from the export while preserving every playable segment', () => {
+        let state = setTrimRange(createVideoEditorState(100, 25), 5, 95);
+        state = addCutAt(state, 20, 10).state;
+        state = addCutAt(state, 60, 5).state;
+        expect(getPlayableSegments(state)).toEqual([
+            { start: 5, end: 20 },
+            { start: 30, end: 60 },
+            { start: 65, end: 95 },
+        ]);
+    });
+
+    test('preview playback jumps to the end of any removed range', () => {
+        let state = addCutAt(createVideoEditorState(100, 25), 20, 10).state;
+        state = addCutAt(state, 60, 5).state;
+        expect(movePreviewTimeOutOfCuts(state, 24)).toBe(30);
+        expect(movePreviewTimeOutOfCuts(state, 64.99)).toBe(65);
+        expect(movePreviewTimeOutOfCuts(state, 40)).toBe(40);
+    });
+
+    test('clips cuts to a smaller trim and removes empty remainders', () => {
+        let state = addCutAt(createVideoEditorState(100, 25), 10, 15).state;
+        state = addCutAt(state, 70, 20).state;
+        state = setTrimRange(state, 20, 75);
+        expect(state.cuts.map((cut) => [cut.start, cut.end])).toEqual([[20, 25], [70, 75]]);
+        state = setTrimRange(state, 30, 60);
+        expect(state.cuts).toEqual([]);
+    });
+
+    test('rejects empty cuts while allowing adjacent cut boundaries', () => {
+        const initial = createVideoEditorState(100, 25);
+        expect(() => addCutAt(initial, 10, 0)).toThrow();
+        let state = addCutAt(initial, 10, 5).state;
+        state = addCutAt(state, 15, 5).state;
+        expect(movePreviewTimeOutOfCuts(state, 10)).toBe(20);
+        expect(getPlayableSegments(state)).toEqual([
+            { start: 0, end: 10 },
+            { start: 20, end: 100 },
+        ]);
+    });
+
+    test('keeps at least one playable frame', () => {
+        const state = createVideoEditorState(10, 25);
+        expect(() => addCutAt(state, 0, 10)).toThrow('playable frame');
+        const cut = addCutAt(state, 1, 2);
+        expect(setCutRange(cut.state, cut.cut.id, 0, 10)).toEqual(cut.state);
+        expect(setTrimRange(cut.state, 1, 2)).toEqual(cut.state);
+    });
+
+    test('accepts exactly one playable frame at repeating frame rates', () => {
+        const state = createVideoEditorState(1, 30);
+        const edited = addCutAt(state, 0, 29 / 30).state;
+        expect(getPlayableSegments(edited)).toEqual([{ start: 0.966666667, end: 1 }]);
+    });
+
+    test('limits an edit to 64 removed ranges', () => {
+        let state = createVideoEditorState(200, 25);
+        for (let index = 0; index < 64; index += 1) state = addCutAt(state, index * 2, 1).state;
+        expect(state.cuts).toHaveLength(64);
+        expect(() => addCutAt(state, 150, 1)).toThrow('64');
+    });
+
+    test('converts timeline percentages and times at frame precision', () => {
+        const state = createVideoEditorState(120, 25);
+        expect(timeToTimelinePercent(state, 60)).toBe(50);
+        expect(timelinePercentToTime(state, 50.01)).toBe(60);
+        expect(timelinePercentToTime(state, 100)).toBe(120);
+    });
+});
+
+describe('video editor history', () => {
+    test('undo and redo restore complete trim and cut states', () => {
+        const initial = createVideoEditorState(100, 25);
+        const trimmed = setTrimRange(initial, 5, 90);
+        const cut = addCutAt(trimmed, 20, 10).state;
+        let history = createEditorHistory(initial);
+        history = commitEditorState(history, trimmed);
+        history = commitEditorState(history, cut);
+
+        history = undoEditorState(history);
+        expect(history.present).toEqual(trimmed);
+        history = undoEditorState(history);
+        expect(history.present).toEqual(initial);
+        history = redoEditorState(history);
+        expect(history.present).toEqual(trimmed);
+        history = redoEditorState(history);
+        expect(history.present).toEqual(cut);
+    });
+
+    test('does not record no-op changes and clears redo after a new edit', () => {
+        const initial = createVideoEditorState(100, 25);
+        const trimmed = setTrimRange(initial, 5, 90);
+        let history = commitEditorState(createEditorHistory(initial), trimmed);
+        history = commitEditorState(history, trimmed);
+        expect(history.past).toHaveLength(1);
+        history = undoEditorState(history);
+        expect(history.future).toHaveLength(1);
+        history = commitEditorState(history, setTrimRange(history.present, 10, 80));
+        expect(history.future).toEqual([]);
+    });
+});

src/main/domain/video-editor.ts

@@ -0,0 +1,268 @@
+export interface EditorCut {
+    id: string;
+    start: number;
+    end: number;
+}
+
+export interface EditorSegment {
+    start: number;
+    end: number;
+}
+
+export interface VideoEditorState {
+    duration: number;
+    fps: number;
+    trimStart: number;
+    trimEnd: number;
+    cuts: EditorCut[];
+}
+
+export interface EditorHistory {
+    past: VideoEditorState[];
+    present: VideoEditorState;
+    future: VideoEditorState[];
+}
+
+const precision = 9;
+const frameTolerance = 1e-8;
+export const maxVideoEditorCuts = 64;
+
+function finitePositive(value: number, name: string): number {
+    if (!Number.isFinite(value) || value <= 0) {
+        throw new Error(`${name} must be greater than zero`);
+    }
+    return value;
+}
+
+function rounded(value: number): number {
+    return Number(value.toFixed(precision));
+}
+
+function clamp(value: number, minimum: number, maximum: number): number {
+    return Math.min(maximum, Math.max(minimum, value));
+}
+
+function snapToFrame(value: number, fps: number): number {
+    return rounded(Math.round(value * fps) / fps);
+}
+
+function cloneState(state: VideoEditorState): VideoEditorState {
+    return {
+        duration: state.duration,
+        fps: state.fps,
+        trimStart: state.trimStart,
+        trimEnd: state.trimEnd,
+        cuts: state.cuts.map((cut) => ({ ...cut })),
+    };
+}
+
+function statesEqual(left: VideoEditorState, right: VideoEditorState): boolean {
+    return left.duration === right.duration
+        && left.fps === right.fps
+        && left.trimStart === right.trimStart
+        && left.trimEnd === right.trimEnd
+        && left.cuts.length === right.cuts.length
+        && left.cuts.every((cut, index) => {
+            const other = right.cuts[index];
+            return cut.id === other.id && cut.start === other.start && cut.end === other.end;
+        });
+}
+
+function nextCutId(cuts: EditorCut[]): string {
+    const used = new Set(cuts.map((cut) => cut.id));
+    let index = cuts.length + 1;
+    while (used.has(`cut-${index}`)) index += 1;
+    return `cut-${index}`;
+}
+
+function overlapsAnotherCut(cuts: EditorCut[], id: string, start: number, end: number): boolean {
+    return cuts.some((cut) => cut.id !== id && start < cut.end && end > cut.start);
+}
+
+function sortCuts(cuts: EditorCut[]): EditorCut[] {
+    return [...cuts].sort((left, right) => left.start - right.start || left.end - right.end || left.id.localeCompare(right.id));
+}
+
+function hasPlayableFrame(state: VideoEditorState, cuts: EditorCut[]): boolean {
+    const removedDuration = cuts.reduce((total, cut) => total + cut.end - cut.start, 0);
+    return state.trimEnd - state.trimStart - removedDuration >= 1 / state.fps - frameTolerance;
+}
+
+export function createVideoEditorState(duration: number, fps: number): VideoEditorState {
+    const safeDuration = finitePositive(duration, 'duration');
+    const safeFps = finitePositive(fps, 'fps');
+    return {
+        duration: rounded(safeDuration),
+        fps: safeFps,
+        trimStart: 0,
+        trimEnd: rounded(safeDuration),
+        cuts: [],
+    };
+}
+
+export function formatEditorTimecode(time: number, fps: number): string {
+    const safeFps = finitePositive(fps, 'fps');
+    let wholeSeconds = Math.floor(Math.max(0, time));
+    let frames = Math.round((Math.max(0, time) - wholeSeconds) * safeFps);
+    const frameBase = Math.max(1, Math.round(safeFps));
+    if (frames >= frameBase) {
+        wholeSeconds += 1;
+        frames = 0;
+    }
+    const hours = Math.floor(wholeSeconds / 3600);
+    const minutes = Math.floor((wholeSeconds % 3600) / 60);
+    const seconds = wholeSeconds % 60;
+    const fields = hours > 0
+        ? [hours, minutes, seconds, frames]
+        : [minutes, seconds, frames];
+    return fields.map((field) => String(field).padStart(2, '0')).join(':');
+}
+
+export function parseEditorTimecode(value: string, fps: number): number {
+    const safeFps = finitePositive(fps, 'fps');
+    const fields = value.trim().split(':');
+    if (fields.length !== 3 && fields.length !== 4) {
+        throw new Error('Timecode must use MM:SS:FF or HH:MM:SS:FF');
+    }
+    const numbers = fields.map((field) => Number(field));
+    if (numbers.some((field) => !Number.isInteger(field) || field < 0)) {
+        throw new Error('Timecode fields must be non-negative integers');
+    }
+    const [hours, minutes, seconds, frames] = numbers.length === 4
+        ? numbers
+        : [0, numbers[0], numbers[1], numbers[2]];
+    if (minutes >= 60 || seconds >= 60 || frames >= Math.max(1, Math.round(safeFps))) {
+        throw new Error('Timecode field is out of range');
+    }
+    return rounded(hours * 3600 + minutes * 60 + seconds + frames / safeFps);
+}
+
+export function setTrimRange(state: VideoEditorState, start: number, end: number): VideoEditorState {
+    if (!Number.isFinite(start) || !Number.isFinite(end)) return state;
+    const frameDuration = 1 / state.fps;
+    const nextStart = clamp(snapToFrame(start, state.fps), 0, state.duration);
+    const nextEnd = clamp(snapToFrame(end, state.fps), 0, state.duration);
+    if (nextEnd - nextStart < frameDuration - frameTolerance) return state;
+    const cuts = state.cuts
+        .map((cut) => ({
+            ...cut,
+            start: Math.max(cut.start, nextStart),
+            end: Math.min(cut.end, nextEnd),
+        }))
+        .filter((cut) => cut.end - cut.start >= frameDuration - frameTolerance);
+    const nextState = {
+        ...state,
+        trimStart: rounded(nextStart),
+        trimEnd: rounded(nextEnd),
+        cuts: sortCuts(cuts),
+    };
+    return hasPlayableFrame(nextState, nextState.cuts) ? nextState : state;
+}
+
+export function addCutAt(state: VideoEditorState, start: number, duration: number): { state: VideoEditorState; cut: EditorCut } {
+    if (state.cuts.length >= maxVideoEditorCuts) throw new Error(`Edit supports up to ${maxVideoEditorCuts} removed ranges`);
+    const nextStart = clamp(snapToFrame(start, state.fps), state.trimStart, state.trimEnd);
+    const nextEnd = clamp(snapToFrame(start + duration, state.fps), state.trimStart, state.trimEnd);
+    const frameDuration = 1 / state.fps;
+    if (!Number.isFinite(start) || !Number.isFinite(duration) || duration <= 0 || nextEnd - nextStart < frameDuration - frameTolerance) {
+        throw new Error('Cut must contain at least one frame');
+    }
+    const cut: EditorCut = { id: nextCutId(state.cuts), start: rounded(nextStart), end: rounded(nextEnd) };
+    if (overlapsAnotherCut(state.cuts, cut.id, cut.start, cut.end)) {
+        throw new Error('Cut overlaps another cut');
+    }
+    const cuts = sortCuts([...state.cuts, cut]);
+    if (!hasPlayableFrame(state, cuts)) throw new Error('Edit must keep at least one playable frame');
+    return {
+        cut,
+        state: { ...state, cuts },
+    };
+}
+
+export function setCutRange(state: VideoEditorState, id: string, start: number, end: number): VideoEditorState {
+    const existing = state.cuts.find((cut) => cut.id === id);
+    if (!existing || !Number.isFinite(start) || !Number.isFinite(end)) return state;
+    const nextStart = clamp(snapToFrame(start, state.fps), state.trimStart, state.trimEnd);
+    const nextEnd = clamp(snapToFrame(end, state.fps), state.trimStart, state.trimEnd);
+    if (nextEnd - nextStart < 1 / state.fps - frameTolerance) return state;
+    if (overlapsAnotherCut(state.cuts, id, nextStart, nextEnd)) return state;
+    const cuts = sortCuts(state.cuts.map((cut) => cut.id === id
+        ? { ...cut, start: rounded(nextStart), end: rounded(nextEnd) }
+        : cut));
+    if (!hasPlayableFrame(state, cuts)) return state;
+    return {
+        ...state,
+        cuts,
+    };
+}
+
+export function removeCut(state: VideoEditorState, id: string): VideoEditorState {
+    if (!state.cuts.some((cut) => cut.id === id)) return state;
+    return { ...state, cuts: state.cuts.filter((cut) => cut.id !== id) };
+}
+
+export function getPlayableSegments(state: VideoEditorState): EditorSegment[] {
+    const segments: EditorSegment[] = [];
+    let cursor = state.trimStart;
+    for (const cut of sortCuts(state.cuts)) {
+        const start = clamp(cut.start, state.trimStart, state.trimEnd);
+        const end = clamp(cut.end, state.trimStart, state.trimEnd);
+        if (start > cursor) segments.push({ start: rounded(cursor), end: rounded(start) });
+        cursor = Math.max(cursor, end);
+    }
+    if (cursor < state.trimEnd) segments.push({ start: rounded(cursor), end: rounded(state.trimEnd) });
+    return segments;
+}
+
+export function getPlayableDuration(state: VideoEditorState): number {
+    return rounded(getPlayableSegments(state).reduce((total, segment) => total + segment.end - segment.start, 0));
+}
+
+export function movePreviewTimeOutOfCuts(state: VideoEditorState, time: number): number {
+    let nextTime = clamp(time, state.trimStart, state.trimEnd);
+    for (const cut of sortCuts(state.cuts)) {
+        if (nextTime >= cut.start && nextTime < cut.end) nextTime = cut.end;
+    }
+    return rounded(clamp(nextTime, state.trimStart, state.trimEnd));
+}
+
+export function timeToTimelinePercent(state: VideoEditorState, time: number): number {
+    return clamp((time / state.duration) * 100, 0, 100);
+}
+
+export function timelinePercentToTime(state: VideoEditorState, percent: number): number {
+    return snapToFrame(clamp(percent, 0, 100) / 100 * state.duration, state.fps);
+}
+
+export function createEditorHistory(initial: VideoEditorState): EditorHistory {
+    return { past: [], present: cloneState(initial), future: [] };
+}
+
+export function commitEditorState(history: EditorHistory, next: VideoEditorState): EditorHistory {
+    if (statesEqual(history.present, next)) return history;
+    return {
+        past: [...history.past, cloneState(history.present)],
+        present: cloneState(next),
+        future: [],
+    };
+}
+
+export function undoEditorState(history: EditorHistory): EditorHistory {
+    const previous = history.past.at(-1);
+    if (!previous) return history;
+    return {
+        past: history.past.slice(0, -1),
+        present: cloneState(previous),
+        future: [cloneState(history.present), ...history.future],
+    };
+}
+
+export function redoEditorState(history: EditorHistory): EditorHistory {
+    const next = history.future[0];
+    if (!next) return history;
+    return {
+        past: [...history.past, cloneState(history.present)],
+        present: cloneState(next),
+        future: history.future.slice(1),
+    };
+}

src/preload.ts

@@ -46,6 +46,49 @@ interface VideoInfo {
     width: number;
     height: number;
     fps: number;
+    hasAudio: boolean;
+    videoCodec: string;
+    audioCodec: string | null;
+    previewCompatible: boolean;
+    variableFrameRate: boolean;
+}
+
+interface VideoEditorMedia {
+    sourceUrl: string;
+    info: VideoInfo;
+    jobId: number;
+    thumbnails: string[];
+    waveform: string | null;
+}
+
+interface VideoEditorAssets {
+    jobId: number;
+    thumbnails: string[];
+    thumbnailSprite: string | null;
+    thumbnailCount: number;
+    pixelWidth: number;
+    pixelHeight: number;
+}
+
+interface VideoEditorWaveform {
+    jobId: number;
+    waveform: string | null;
+    pixelWidth: number;
+    pixelHeight: number;
+}
+
+interface VideoEditorAssetProfile {
+    timelineWidth: number;
+    trackHeight: number;
+    pixelRatio: number;
+}
+
+interface VideoEditExportRequest {
+    inputFile: string;
+    outputFile?: string;
+    trimStart: number;
+    trimEnd: number;
+    cuts: Array<{ id: string; start: number; end: number }>;
 }
 
 // Expose protected methods to renderer
@@ -112,6 +155,12 @@ contextBridge.exposeInMainWorld('api', {
     // Video Cutter
     getVideoInfo: (filePath: string): Promise<VideoInfo | null> => ipcRenderer.invoke('get-video-info', filePath),
     extractFrame: (filePath: string, timeSeconds: number): Promise<string | null> => ipcRenderer.invoke('extract-frame', filePath, timeSeconds),
+    prepareVideoEditorMedia: (filePath: string): Promise<VideoEditorMedia | null> => ipcRenderer.invoke('prepare-video-editor-media', filePath),
+    prepareVideoEditorWaveform: (filePath: string, jobId: number): Promise<VideoEditorWaveform | null> => ipcRenderer.invoke('prepare-video-editor-waveform', filePath, jobId),
+    prepareVideoEditorAssets: (filePath: string, jobId: number, profile: VideoEditorAssetProfile): Promise<VideoEditorAssets | null> => ipcRenderer.invoke('prepare-video-editor-assets', filePath, jobId, profile),
+    cancelVideoEditorAssets: (jobId: number): Promise<boolean> => ipcRenderer.invoke('cancel-video-editor-assets', jobId),
+    exportVideoEdit: (request: VideoEditExportRequest): Promise<{ success: boolean; outputFile: string | null; cancelled?: boolean }> => ipcRenderer.invoke('export-video-edit', request),
+    cancelVideoEdit: (): Promise<boolean> => ipcRenderer.invoke('cancel-video-edit'),
     cutVideo: (inputFile: string, startTime: number, endTime: number): Promise<{ success: boolean; outputFile: string | null }> =>
         ipcRenderer.invoke('cut-video', inputFile, startTime, endTime),
 

src/renderer-globals.d.ts

@@ -165,6 +165,49 @@ interface VideoInfo {
     width: number;
     height: number;
     fps: number;
+    hasAudio: boolean;
+    videoCodec: string;
+    audioCodec: string | null;
+    previewCompatible: boolean;
+    variableFrameRate: boolean;
+}
+
+interface VideoEditorMedia {
+    sourceUrl: string;
+    info: VideoInfo;
+    jobId: number;
+    thumbnails: string[];
+    waveform: string | null;
+}
+
+interface VideoEditorAssets {
+    jobId: number;
+    thumbnails: string[];
+    thumbnailSprite: string | null;
+    thumbnailCount: number;
+    pixelWidth: number;
+    pixelHeight: number;
+}
+
+interface VideoEditorWaveform {
+    jobId: number;
+    waveform: string | null;
+    pixelWidth: number;
+    pixelHeight: number;
+}
+
+interface VideoEditorAssetProfile {
+    timelineWidth: number;
+    trackHeight: number;
+    pixelRatio: number;
+}
+
+interface VideoEditExportRequest {
+    inputFile: string;
+    outputFile?: string;
+    trimStart: number;
+    trimEnd: number;
+    cuts: Array<{ id: string; start: number; end: number }>;
 }
 
 interface ClipDialogData {
@@ -375,6 +418,12 @@ interface ApiBridge {
     onAutoVodScanCompleted(callback: (info: { queuedCount: number }) => void): void;
     getVideoInfo(filePath: string): Promise<VideoInfo | null>;
     extractFrame(filePath: string, timeSeconds: number): Promise<string | null>;
+    prepareVideoEditorMedia(filePath: string): Promise<VideoEditorMedia | null>;
+    prepareVideoEditorWaveform(filePath: string, jobId: number): Promise<VideoEditorWaveform | null>;
+    prepareVideoEditorAssets(filePath: string, jobId: number, profile: VideoEditorAssetProfile): Promise<VideoEditorAssets | null>;
+    cancelVideoEditorAssets(jobId: number): Promise<boolean>;
+    exportVideoEdit(request: VideoEditExportRequest): Promise<{ success: boolean; outputFile: string | null; cancelled?: boolean }>;
+    cancelVideoEdit(): Promise<boolean>;
     cutVideo(inputFile: string, startTime: number, endTime: number): Promise<{ success: boolean; outputFile: string | null }>;
     mergeVideos(inputFiles: string[], outputFile: string): Promise<{ success: boolean; outputFile: string | null }>;
     getVersion(): Promise<string>;

src/renderer-locale-de.ts

@@ -57,7 +57,7 @@ const UI_TEXT_DE = {
         commandPaletteHint: 'Auf/Ab zum Navigieren, Enter zum Ausführen, Esc zum Schließen',
         mergeTitle: 'Videos zusammenfügen',
         mergeDesc: 'Wähle mehrere Videos aus, um sie zu einem Video zusammenzufügen. Die Reihenfolge kann geändert werden.',
-        mergeAdd: '+ Videos hinzufügen',
+        mergeAdd: 'Videos hinzufügen',
         designTitle: 'Design',
         themeLabel: 'Theme',
         themeLight: 'Hell',
@@ -499,17 +499,58 @@ const UI_TEXT_DE = {
         previewLoading: 'Lade Vorschau...',
         previewUnavailable: 'Vorschau nicht verfügbar',
         previewAlt: 'Vorschau',
-        cutting: 'Schneidet...',
+        cutting: 'Exportiert…',
-        cut: 'Schneiden',
+        cut: 'Video exportieren',
-        cutSuccess: 'Video erfolgreich geschnitten!',
+        cutSuccess: 'Video erfolgreich exportiert!',
-        cutFailed: 'Fehler beim Schneiden des Videos.',
+        cutFailed: 'Fehler beim Exportieren des Videos.',
         infoDuration: 'Dauer',
         infoResolution: 'Auflösung',
         infoFps: 'FPS',
-        infoSelection: 'Auswahl',
+        infoSelection: 'Ausgabe',
-        startLabel: 'Start:',
+        startLabel: 'Start',
-        endLabel: 'Ende:',
+        endLabel: 'Ende',
-        filePathPlaceholder: 'Keine Datei ausgewählt…'
+        filePathPlaceholder: 'Keine Datei ausgewählt…',
+        editorTitle: 'Trimmen & schneiden',
+        previewMode: 'Schnittvorschau',
+        previewModeHint: 'Entfernte Bereiche überspringen',
+        globalTrim: 'Gesamtauswahl',
+        cutsLabel: 'Entfernte Bereiche',
+        noCuts: 'Noch keine Schnitte',
+        newCut: 'Neuer Schnitt',
+        cutLabel: 'Schnitt',
+        removeCut: 'Schnitt entfernen',
+        videoTrack: 'VIDEO',
+        audioTrack: 'AUDIO',
+        noAudio: 'Keine Audiospur',
+        loadingMedia: 'Video wird vorbereitet…',
+        speedLabel: 'Geschwindigkeit',
+        play: 'Abspielen',
+        pause: 'Pausieren',
+        stop: 'Stopp',
+        rewind10: '10 Sekunden zurück',
+        forward10: '10 Sekunden vor',
+        mute: 'Stummschalten',
+        unmute: 'Ton einschalten',
+        volume: 'Lautstärke',
+        playerSettings: 'Player-Einstellungen',
+        fullscreen: 'Vollbild',
+        undo: 'Rückgängig',
+        redo: 'Wiederholen',
+        zoomOut: 'Timeline verkleinern',
+        zoomIn: 'Timeline vergrößern',
+        zoom: 'Timeline-Zoom',
+        trimStart: 'Startgrenze verschieben',
+        trimEnd: 'Endgrenze verschieben',
+        export: 'Video exportieren',
+        cancel: 'Abbrechen',
+        exportSuccess: 'Video wurde erfolgreich exportiert.',
+        exportFailed: 'Der Videoexport ist fehlgeschlagen.',
+        invalidRange: 'Der Zeitbereich ist ungültig oder überschneidet einen anderen Schnitt.',
+        unsupportedFile: 'Bitte eine unterstützte Videodatei auswählen.',
+        discardTitle: 'Aktuellen Schnitt verwerfen?',
+        discardMessage: 'Beim Öffnen eines anderen Videos gehen die aktuellen Schnittänderungen verloren.',
+        discardCancel: 'Aktuelles Video behalten',
+        discardConfirm: 'Verwerfen und öffnen'
     },
     merge: {
         empty: 'Keine Videos ausgewahlt',

src/renderer-locale-en.ts

@@ -57,7 +57,7 @@ const UI_TEXT_EN = {
         commandPaletteHint: 'Up/Down to navigate, Enter to run, Esc to close',
         mergeTitle: 'Merge videos',
         mergeDesc: 'Select multiple videos to merge into one file. You can change the order before merging.',
-        mergeAdd: '+ Add videos',
+        mergeAdd: 'Add videos',
         designTitle: 'Design',
         themeLabel: 'Theme',
         themeLight: 'Light',
@@ -499,17 +499,58 @@ const UI_TEXT_EN = {
         previewLoading: 'Loading preview...',
         previewUnavailable: 'Preview unavailable',
         previewAlt: 'Preview',
-        cutting: 'Cutting...',
+        cutting: 'Exporting…',
-        cut: 'Cut',
+        cut: 'Export video',
-        cutSuccess: 'Video cut successfully!',
+        cutSuccess: 'Video exported successfully!',
-        cutFailed: 'Failed to cut video.',
+        cutFailed: 'Failed to export video.',
         infoDuration: 'Duration',
         infoResolution: 'Resolution',
         infoFps: 'FPS',
-        infoSelection: 'Selection',
+        infoSelection: 'Output',
-        startLabel: 'Start:',
+        startLabel: 'Start',
-        endLabel: 'End:',
+        endLabel: 'End',
-        filePathPlaceholder: 'No file selected…'
+        filePathPlaceholder: 'No file selected…',
+        editorTitle: 'Trim & cut',
+        previewMode: 'Cut preview',
+        previewModeHint: 'Skip removed ranges',
+        globalTrim: 'Global selection',
+        cutsLabel: 'Removed ranges',
+        noCuts: 'No cuts yet',
+        newCut: 'New cut',
+        cutLabel: 'Cut',
+        removeCut: 'Remove cut',
+        videoTrack: 'VIDEO',
+        audioTrack: 'AUDIO',
+        noAudio: 'No audio track',
+        loadingMedia: 'Preparing video…',
+        speedLabel: 'Playback speed',
+        play: 'Play',
+        pause: 'Pause',
+        stop: 'Stop',
+        rewind10: 'Back 10 seconds',
+        forward10: 'Forward 10 seconds',
+        mute: 'Mute',
+        unmute: 'Unmute',
+        volume: 'Volume',
+        playerSettings: 'Player settings',
+        fullscreen: 'Fullscreen',
+        undo: 'Undo',
+        redo: 'Redo',
+        zoomOut: 'Zoom timeline out',
+        zoomIn: 'Zoom timeline in',
+        zoom: 'Timeline zoom',
+        trimStart: 'Move start boundary',
+        trimEnd: 'Move end boundary',
+        export: 'Export video',
+        cancel: 'Cancel',
+        exportSuccess: 'Video exported successfully.',
+        exportFailed: 'Video export failed.',
+        invalidRange: 'The time range is invalid or overlaps another cut.',
+        unsupportedFile: 'Select a supported video file.',
+        discardTitle: 'Discard the current edit?',
+        discardMessage: 'Opening another video will discard the current editing changes.',
+        discardCancel: 'Keep current video',
+        discardConfirm: 'Discard and open'
     },
     merge: {
         empty: 'No videos selected',

src/renderer-shared.ts

@@ -70,8 +70,6 @@ let queueDragDropInitialized = false;
 
 let cutterFile: string | null = null;
 let cutterVideoInfo: VideoInfo | null = null;
-let cutterStartTime = 0;
-let cutterEndTime = 0;
 let isCutting = false;
 
 let mergeFiles: string[] = [];

src/renderer-streamers.ts

@@ -485,13 +485,16 @@ function initCutterDragDrop(): void {
 
         const files = Array.from(e.dataTransfer.files || []);
         if (files.length === 0) return;
-        // First video-ish file wins
+        const allowed = /\.(mp4|m4v|mov|webm|mkv|ts|avi)$/i;
-        const allowed = /\.(mp4|mkv|ts|mov|avi)$/i;
+        const file = files.find((entry) => allowed.test(entry.name));
-        const file = files.find((f) => allowed.test(f.name)) || files[0];
+        if (!file) {
+            showAppToast(UI_TEXT.cutter.unsupportedFile, 'warn');
+            return;
+        }
         const filePath = window.api.getPathForFile(file);
         if (!filePath) return;
 
-        const loader = (window as unknown as { loadCutterFromPath?: (p: string) => Promise<void> }).loadCutterFromPath;
+        const loader = (window as unknown as { requestCutterVideoReplacement?: (p: string) => Promise<void> }).requestCutterVideoReplacement;
         if (typeof loader === 'function') {
             await loader(filePath);
         }

src/renderer-texts.ts

@@ -176,9 +176,42 @@ function applyLanguageToStaticUI(): void {
     setText('cutterInfoResolutionLabel', UI_TEXT.cutter.infoResolution);
     setText('cutterInfoFpsLabel', UI_TEXT.cutter.infoFps);
     setText('cutterInfoSelectionLabel', UI_TEXT.cutter.infoSelection);
+    setText('cutterDiscardTitle', UI_TEXT.cutter.discardTitle);
+    setText('cutterDiscardMessage', UI_TEXT.cutter.discardMessage);
+    setText('cutterDiscardCancelBtn', UI_TEXT.cutter.discardCancel);
+    setText('cutterDiscardConfirmBtn', UI_TEXT.cutter.discardConfirm);
     setText('cutterStartLabel', UI_TEXT.cutter.startLabel);
     setText('cutterEndLabel', UI_TEXT.cutter.endLabel);
     setText('btnCut', UI_TEXT.cutter.cut);
+    setText('cutterEditHeading', UI_TEXT.cutter.editorTitle);
+    setText('cutterPreviewModeLabel', UI_TEXT.cutter.previewMode);
+    setText('cutterPreviewModeHint', UI_TEXT.cutter.previewModeHint);
+    setText('cutterGlobalTrimLabel', UI_TEXT.cutter.globalTrim);
+    setText('cutterCutsLabel', UI_TEXT.cutter.cutsLabel);
+    setText('cutterCutEmpty', UI_TEXT.cutter.noCuts);
+    setText('cutterVideoTrackLabel', UI_TEXT.cutter.videoTrack);
+    setText('cutterAudioTrackLabel', UI_TEXT.cutter.audioTrack);
+    setText('cutterAudioEmpty', UI_TEXT.cutter.noAudio);
+    setText('cutterLoadingLabel', UI_TEXT.cutter.loadingMedia);
+    setText('cutterSpeedLabel', UI_TEXT.cutter.speedLabel);
+    setAriaLabel('cutterPlayBtn', UI_TEXT.cutter.play);
+    setAriaLabel('cutterStopBtn', UI_TEXT.cutter.stop);
+    setAriaLabel('cutterRewindBtn', UI_TEXT.cutter.rewind10);
+    setAriaLabel('cutterForwardBtn', UI_TEXT.cutter.forward10);
+    setAriaLabel('cutterMuteBtn', UI_TEXT.cutter.mute);
+    setAriaLabel('cutterVolume', UI_TEXT.cutter.volume);
+    setAriaLabel('cutterSettingsBtn', UI_TEXT.cutter.playerSettings);
+    setAriaLabel('cutterFullscreenBtn', UI_TEXT.cutter.fullscreen);
+    setAriaLabel('cutterUndoBtn', UI_TEXT.cutter.undo);
+    setAriaLabel('cutterRedoBtn', UI_TEXT.cutter.redo);
+    setAriaLabel('cutterZoomOutBtn', UI_TEXT.cutter.zoomOut);
+    setAriaLabel('cutterZoomInBtn', UI_TEXT.cutter.zoomIn);
+    setAriaLabel('cutterZoom', UI_TEXT.cutter.zoom);
+    setAriaLabel('cutterTrimStartHandle', UI_TEXT.cutter.trimStart);
+    setAriaLabel('cutterTrimEndHandle', UI_TEXT.cutter.trimEnd);
+    setText('cutterCancelExportBtn', UI_TEXT.cutter.cancel);
+    setAriaLabel('cutterNewCutBtn', UI_TEXT.cutter.newCut);
+    setTitle('cutterNewCutBtn', UI_TEXT.cutter.newCut);
     setText('mergeTitle', UI_TEXT.static.mergeTitle);
     setText('mergeDesc', UI_TEXT.static.mergeDesc);
     setText('mergeAddBtn', UI_TEXT.static.mergeAdd);
@@ -413,6 +446,9 @@ function applyLanguageToStaticUI(): void {
     if (typeof workspaceSync === 'function') {
         workspaceSync(activeTabId.replace(/Tab$/, ''));
     }
+    if (typeof updateCutterPlayUi === 'function') updateCutterPlayUi();
+    if (typeof updateCutterMuteUi === 'function') updateCutterMuteUi();
+    if (typeof renderCutterEditor === 'function') renderCutterEditor();
 }
 
 function localizeCurrentStatusText(current: string): string {

src/renderer.ts

@@ -75,6 +75,7 @@ async function init(): Promise<void> {
     loadVodScrollPositions();
     initVodScrollTracking();
     initCutterDragDrop();
+    initCutterEditor();
 
     // Restore last active tab from previous session (default 'vods')
     initTopNavActiveIndicator();
@@ -531,6 +532,12 @@ function renderChatViewerList(messages: ChatViewerMessage[]): void {
 
 function closeTopmostOpenModal(): boolean {
     // Try each known modal in priority order
+    const cutterDiscardModal = document.getElementById('cutterDiscardModal');
+    if (cutterDiscardModal?.classList.contains('show')) {
+        resolveCutterDiscard(false);
+        return true;
+    }
+
     const commandPaletteModal = document.getElementById('commandPaletteModal');
     if (commandPaletteModal?.classList.contains('show')) {
         const closeCp = (window as unknown as { closeCommandPalette?: () => void }).closeCommandPalette;
@@ -974,6 +981,7 @@ function focusWorkspaceTarget(id: string, source?: HTMLElement): void {
 }
 
 function showTab(tab: string): void {
+    if (tab !== 'cutter' && byId('cutterTab').classList.contains('active') && typeof deactivateCutterEditor === 'function') deactivateCutterEditor();
     queryAll('.nav-item').forEach((i) => {
         i.classList.remove('active');
         i.removeAttribute('aria-current');
@@ -990,6 +998,7 @@ function showTab(tab: string): void {
     navItem.setAttribute('aria-current', 'page');
     syncTopNavActiveIndicator();
     byId(tab + 'Tab').classList.add('active');
+    if (tab === 'cutter' && typeof activateCutterEditor === 'function') activateCutterEditor();
     syncWorkspaceChrome(tab);
     scheduleSegmentedIndicatorsSync();
 
@@ -1671,146 +1680,6 @@ function initSegmentedIndicators(): void {
     window.addEventListener('resize', scheduleSegmentedIndicatorsSync);
 }
 
-async function loadCutterFromPath(filePath: string): Promise<void> {
-    if (!filePath) return;
-
-    cutterFile = filePath;
-    byId<HTMLInputElement>('cutterFilePath').value = filePath;
-
-    const info = await window.api.getVideoInfo(filePath);
-    if (!info) {
-        alert(UI_TEXT.cutter.videoInfoFailed);
-        return;
-    }
-
-    cutterVideoInfo = info;
-    cutterStartTime = 0;
-    cutterEndTime = info.duration;
-
-    byId('cutterInfo').classList.add('shown');
-    byId('timelineContainer').classList.add('shown');
-    byId('btnCut').disabled = false;
-
-    byId('infoDuration').textContent = formatTime(info.duration);
-    byId('infoResolution').textContent = `${info.width}x${info.height}`;
-    byId('infoFps').textContent = Math.round(info.fps);
-    byId('infoSelection').textContent = formatTime(info.duration);
-
-    byId<HTMLInputElement>('startTime').value = '00:00:00';
-    byId<HTMLInputElement>('endTime').value = formatTime(info.duration);
-
-    updateTimeline();
-    await updatePreview(0);
-}
-
-async function selectCutterVideo(): Promise<void> {
-    const filePath = await window.api.selectVideoFile();
-    if (!filePath) return;
-    await loadCutterFromPath(filePath);
-}
-
-function formatTime(seconds: number): string {
-    const h = Math.floor(seconds / 3600);
-    const m = Math.floor((seconds % 3600) / 60);
-    const s = Math.floor(seconds % 60);
-    return `${h.toString().padStart(2, '0')}:${m.toString().padStart(2, '0')}:${s.toString().padStart(2, '0')}`;
-}
-
-function parseTime(timeStr: string): number {
-    const parts = timeStr.split(':').map((p: string) => parseInt(p, 10) || 0);
-    if (parts.length === 3) {
-        return parts[0] * 3600 + parts[1] * 60 + parts[2];
-    }
-
-    return 0;
-}
-
-function updateTimeline(): void {
-    if (!cutterVideoInfo) {
-        return;
-    }
-
-    const selection = byId('timelineSelection');
-    const startPercent = (cutterStartTime / cutterVideoInfo.duration) * 100;
-    const endPercent = (cutterEndTime / cutterVideoInfo.duration) * 100;
-
-    selection.style.left = startPercent + '%';
-    selection.style.width = (endPercent - startPercent) + '%';
-
-    const duration = cutterEndTime - cutterStartTime;
-    byId('infoSelection').textContent = formatTime(duration);
-}
-
-function updateTimeFromInput(): void {
-    const startStr = byId<HTMLInputElement>('startTime').value;
-    const endStr = byId<HTMLInputElement>('endTime').value;
-
-    cutterStartTime = Math.max(0, parseTime(startStr));
-    cutterEndTime = Math.min(cutterVideoInfo?.duration || 0, parseTime(endStr));
-
-    if (cutterEndTime <= cutterStartTime) {
-        cutterEndTime = cutterStartTime + 1;
-    }
-
-    updateTimeline();
-}
-
-async function seekTimeline(event: MouseEvent): Promise<void> {
-    if (!cutterVideoInfo) {
-        return;
-    }
-
-    const timeline = byId<HTMLElement>('timeline');
-    const rect = timeline.getBoundingClientRect();
-    const percent = (event.clientX - rect.left) / rect.width;
-    const time = percent * cutterVideoInfo.duration;
-
-    byId('timelineCurrent').style.left = (percent * 100) + '%';
-    await updatePreview(time);
-}
-
-async function updatePreview(time: number): Promise<void> {
-    if (!cutterFile) {
-        return;
-    }
-
-    const preview = byId('cutterPreview');
-    applyHtml(preview, `<div class="placeholder"><p>${escapeHtml(UI_TEXT.cutter.previewLoading)}</p></div>`);
-
-    const frame = await window.api.extractFrame(cutterFile, time);
-    if (frame) {
-        applyHtml(preview, `<img src="${escapeHtml(frame)}" alt="${escapeHtml(UI_TEXT.cutter.previewAlt)}">`);
-        return;
-    }
-
-    applyHtml(preview, `<div class="placeholder"><p>${escapeHtml(UI_TEXT.cutter.previewUnavailable)}</p></div>`);
-}
-
-async function startCutting(): Promise<void> {
-    if (!cutterFile || isCutting) {
-        return;
-    }
-
-    isCutting = true;
-    byId('btnCut').disabled = true;
-    byId('btnCut').textContent = UI_TEXT.cutter.cutting;
-    byId('cutProgress').classList.add('show');
-
-    const result = await window.api.cutVideo(cutterFile, cutterStartTime, cutterEndTime);
-
-    isCutting = false;
-    byId('btnCut').disabled = false;
-    byId('btnCut').textContent = UI_TEXT.cutter.cut;
-    byId('cutProgress').classList.remove('show');
-
-    if (result.success) {
-        alert(`${UI_TEXT.cutter.cutSuccess}\n\n${result.outputFile}`);
-        return;
-    }
-
-    alert(UI_TEXT.cutter.cutFailed);
-}
-
 async function addMergeFiles(): Promise<void> {
     const files = await window.api.selectMultipleVideos();
     if (!files || files.length === 0) {

src/workspace.css

@@ -190,6 +190,16 @@ a:focus-visible {
     box-shadow: none;
 }
 
+input.cutter-volume:focus-visible {
+    outline: none;
+    box-shadow: none;
+}
+
+.cutter-volume-control:has(.cutter-volume:focus-visible) .cutter-player-button {
+    background: rgba(255, 255, 255, 0.14);
+    box-shadow: inset 0 0 0 2px var(--workspace-primary);
+}
+
 button:disabled,
 input:disabled,
 select:disabled,
@@ -1817,11 +1827,14 @@ input[type="checkbox"].vod-select-checkbox:focus-visible {
 }
 
 .clip-input,
-.cutter-container,
 .merge-container {
     max-width: 760px;
 }
 
+.cutter-container {
+    max-width: none;
+}
+
 .clip-input {
     margin: 0;
     padding: 0;
@@ -2168,6 +2181,44 @@ input[type="checkbox"].vod-select-checkbox:focus-visible {
     margin-top: 18px;
 }
 
+.cutter-discard-modal {
+    max-width: 460px;
+}
+
+.cutter-discard-modal h2 {
+    margin: 0 0 10px;
+}
+
+.cutter-discard-modal p {
+    margin: 0;
+    color: var(--workspace-text-muted);
+    line-height: 1.5;
+}
+
+#cutterDiscardCancelBtn {
+    color: #000;
+    background: var(--workspace-primary);
+    border-color: var(--workspace-primary);
+}
+
+#cutterDiscardCancelBtn:hover:not(:disabled) {
+    color: #000;
+    background: var(--workspace-primary-hover);
+    border-color: var(--workspace-primary-hover);
+}
+
+#cutterDiscardConfirmBtn {
+    color: #000;
+    background: var(--workspace-danger);
+    border-color: var(--workspace-danger);
+}
+
+#cutterDiscardConfirmBtn:hover:not(:disabled) {
+    color: #000;
+    background: #f38d8d;
+    border-color: #f38d8d;
+}
+
 .update-modal {
     background: var(--workspace-panel-raised);
     border-color: var(--workspace-border-strong);
@@ -2586,6 +2637,15 @@ input[type="checkbox"].vod-select-checkbox:focus-visible {
         transition-delay: 0s !important;
     }
 
+    .cutter-volume {
+        transition: width 220ms cubic-bezier(0.2, 0.75, 0.25, 1), margin 220ms cubic-bezier(0.2, 0.75, 0.25, 1), opacity 150ms ease, visibility 0s linear 220ms !important;
+    }
+
+    .cutter-volume-control:hover .cutter-volume,
+    .cutter-volume-control:focus-within .cutter-volume {
+        transition-delay: 0s !important;
+    }
+
     .top-nav::before {
         transition: transform 420ms cubic-bezier(0.22, 0.76, 0.22, 1), width 420ms cubic-bezier(0.22, 0.76, 0.22, 1), height 420ms cubic-bezier(0.22, 0.76, 0.22, 1) !important;
     }
@@ -2951,8 +3011,9 @@ input[type="checkbox"].vod-select-checkbox:focus-visible {
 }
 
 #settingsTab .language-picker .lang-option > span:not(.flag-icon) {
-    color: #fff;
+    color: var(--workspace-text-muted);
-    mix-blend-mode: difference;
+    mix-blend-mode: normal;
+    transition: color 120ms ease;
 }
 
 #settingsTab .language-picker .lang-option:hover {
@@ -2966,6 +3027,10 @@ input[type="checkbox"].vod-select-checkbox:focus-visible {
     box-shadow: none;
 }
 
+#settingsTab .language-picker .lang-option.active > span:not(.flag-icon) {
+    color: var(--workspace-primary-text);
+}
+
 #settingsTab .language-picker .lang-option.active:hover {
     background: transparent;
 }