fix: multi-level account rotation + clear failed-accounts per batch + size-sort staleness

Three state bugs found during audit:

  1. _failedAccounts / _accountOverrides survived across batches. A
     rate-limited account from batch 1 stayed permanently blacklisted
     for the rest of the app session, so batch 2 skipped straight to
     the fallback even after the original recovered. Now cleared in
     startBatch so each run evaluates accounts fresh.

  2. Account rotation was one level deep. With three accounts [A,B,C]
     on the same hoster and A + B both failing, the job errored out
     — C was never tried. The fallback-retry was a single if-block.
     Replaced with a while-loop that keeps asking main for the next
     override and rotating until every account is exhausted.

  3. Queue sort cache included 'size' as a static key, but bytesTotal
     goes 0 → actual when previews resolve. A queue sorted by size
     during preview would cache the all-zeros order and never update.
     Removed size from _STATIC_SORT_KEYS — it now re-sorts per render
     like status/speed/progress.

lib/upload-manager.js

@@ -132,6 +132,12 @@ class UploadManager extends EventEmitter {
     this.globalSemaphore = null;
     this.globalThrottle = null;
     this.lastStartTime = {};
+    // Reset account-rotation state each batch. Otherwise a previously failed
+    // account (e.g. rate-limited during the last batch) stays permanently
+    // blacklisted until the app restarts — every upload would silently skip
+    // straight to the fallback even after the original recovered.
+    this._failedAccounts.clear();
+    this._accountOverrides.clear();
 
     const { signal } = this.abortController;
     const batchId = `batch-${Date.now()}`;
@@ -461,14 +467,17 @@ class UploadManager extends EventEmitter {
         return;
       }
 
-      // Account fallback: if this account hasn't failed before, try switching
+      // Account rotation: mark the current account failed, wait for main to
-      if (task.accountId && !this._failedAccounts.has(task.hoster + ':' + task.accountId)) {
+      // resolve the next fallback, then retry. Loop so A → B → C → ... works
+      // for hosters with 3+ accounts (the old code only did one level: A → B
+      // and stopped, even if C would have worked).
+      while (task.accountId && !this._failedAccounts.has(task.hoster + ':' + task.accountId)) {
+        if (signal.aborted || this.stopAfterActive) break;
         this._failedAccounts.set(task.hoster + ':' + task.accountId, true);
         this.emit('account-failed', { hoster: task.hoster, accountId: task.accountId });
-        // Wait briefly for switchAccount() to be called from main process
         await this._sleep(800, signal);
         const override = this._accountOverrides.get(task.hoster);
-        if (override && !this._failedAccounts.has(task.hoster + ':' + override.id)) {
+        if (!override || this._failedAccounts.has(task.hoster + ':' + override.id)) break;
         // Switch to fallback account and retry this file
         task.accountId = override.id;
         task.username = override.username;
@@ -479,7 +488,9 @@ class UploadManager extends EventEmitter {
           speedKbs: 0, elapsed: 0, remaining: 0,
           error: 'Account-Wechsel zu Fallback', result: null, attempt: 1, maxAttempts
         });
-          // Re-run retry loop with new account
+        // Retry loop with the new account. On exhausted failure, the while
+        // loop iterates: marks this account failed too, asks main for the next
+        // fallback, and so on.
         for (let attempt = 1; attempt <= maxAttempts; attempt++) {
           if (signal.aborted || this.stopAfterActive) break;
           if (attempt > 1) {
@@ -495,7 +506,8 @@ class UploadManager extends EventEmitter {
             let lastBytes = 0;
             let lastSpeedTime = jobStart;
             let currentSpeedKbs = 0;
-              this.activeJobs.set(uploadId, { jobId, speedKbs: 0, bytesUploaded: 0 });
+            const activeEntry = { jobId, speedKbs: 0, bytesUploaded: 0 };
+            this.activeJobs.set(uploadId, activeEntry);
 
             const progressCb = (bytesUploaded, bytesTotal) => {
               const now = Date.now();
@@ -505,7 +517,8 @@ class UploadManager extends EventEmitter {
                 lastBytes = bytesUploaded;
                 lastSpeedTime = now;
               }
-                this.activeJobs.set(uploadId, { jobId, speedKbs: currentSpeedKbs, bytesUploaded });
+              activeEntry.speedKbs = currentSpeedKbs;
+              activeEntry.bytesUploaded = bytesUploaded;
               const elapsed = Math.round((now - jobStart) / 1000);
               const remaining = currentSpeedKbs > 0 ? Math.round((bytesTotal - bytesUploaded) / (currentSpeedKbs * 1024)) : 0;
               this._emitProgress(uploadId, fileName, task.hoster, {
@@ -536,7 +549,6 @@ class UploadManager extends EventEmitter {
           }
         }
       }
-      }
 
       const error = lastError && lastError.message ? lastError.message : 'Unbekannter Fehler';
       emitFinalStatus('error', { error });

renderer/app.js

@@ -1062,13 +1062,13 @@ function _onQueueScroll() {
 const _collatorDE = new Intl.Collator('de', { sensitivity: 'base', numeric: true });
 const _collatorSimple = new Intl.Collator('de');
 
-// Queue sort memoization. Keys that don't change during upload (filename, host,
+// Queue sort memoization. Keys that don't change after a job enters the queue
-// size) reuse the cached result across progress-driven re-renders. Dynamic keys
+// (filename, host) reuse the cached result across progress-driven re-renders.
-// (status/speed/progress) are recomputed each call since the sort order itself
+// Dynamic keys (status/speed/progress) AND size (which goes 0 → actual when
-// moves every tick. For a queue of 1000+ jobs sorted by filename, this skips
+// previews resolve / upload starts) are recomputed each call — otherwise a
-// the Collator-based O(n log n) sort on every 200ms progress render.
+// queue sorted by size during previews would be stuck in all-zeros order.
 let _queueSortCache = { sig: '', result: [] };
-const _STATIC_SORT_KEYS = new Set(['filename', 'host', 'size']);
+const _STATIC_SORT_KEYS = new Set(['filename', 'host']);
 
 function sortQueueJobs(jobs) {
   const { key, direction } = queueSortState;