fix(downloads): stabilize remaining metric updates

src/renderer/ui/RollingMetricValue.tsx

@@ -22,6 +22,10 @@ export function getRollingMetricDirection(previous: number, next: number): Rolli
   return "none";
 }
 
+export function shouldAnimateRollingMetric(previousValue: string, nextValue: string): boolean {
+  return previousValue !== nextValue;
+}
+
 export function RollingMetricValue({ numericValue, value }: RollingMetricValueProps): ReactElement {
   const previousRef = useRef({ numericValue, value });
   const sequenceRef = useRef(0);
@@ -31,8 +35,8 @@ export function RollingMetricValue({ numericValue, value }: RollingMetricValuePr
 
   useMetricLayoutEffect(() => {
     const previous = previousRef.current;
-    if (previous.value === value && previous.numericValue === numericValue) return;
     previousRef.current = { numericValue, value };
+    if (!shouldAnimateRollingMetric(previous.value, value)) return;
     const direction = getRollingMetricDirection(previous.numericValue, numericValue);
     if (direction === "none") {
       setTransition(null);

src/renderer/views/downloads/downloads-model.ts

@@ -117,8 +117,11 @@ export function getRemainingDownloadBytes(items: Iterable<DownloadItem>): { byte
 }
 
 export function formatRemainingDownloadBytes(summary: { bytes: number; unknownItems: number }): string {
-  if (summary.unknownItems <= 0) return humanSize(summary.bytes);
-  return summary.bytes > 0 ? `≥ ${humanSize(summary.bytes)}` : "Unbekannt";
+  const value = summary.bytes >= 1024 ** 4
+    ? `${(summary.bytes / 1024 ** 4).toFixed(4)} TB`
+    : humanSize(summary.bytes);
+  if (summary.unknownItems <= 0) return value;
+  return summary.bytes > 0 ? `≥ ${value}` : "Unbekannt";
 }
 
 export function formatRemainingDownloadTooltip(summary: { bytes: number; unknownItems: number }): string {

tests/downloads-view.test.tsx

@@ -69,7 +69,7 @@ import {
   formatHosterLabel,
   normalizeDownloadServiceLabel
 } from "../src/renderer/download-format";
-import { getRollingMetricDirection } from "../src/renderer/ui/RollingMetricValue";
+import { getRollingMetricDirection, shouldAnimateRollingMetric } from "../src/renderer/ui/RollingMetricValue";
 import { SlidingSelection } from "../src/renderer/ui/SlidingSelection";
 
 const now = new Date(2026, 7, 10, 12, 0, 0, 0).getTime();
@@ -153,6 +153,11 @@ describe("Downloadtabellen-Spalten", () => {
 });
 
 describe("rollende Downloadkennzahlen", () => {
+  it("does not animate raw byte changes while the visible value stays unchanged", () => {
+    expect(shouldAnimateRollingMetric("1.111 TB", "1.111 TB")).toBe(false);
+    expect(shouldAnimateRollingMetric("1.111 TB", "1.110 TB")).toBe(true);
+  });
+
   it("moves increasing values up and decreasing values down", () => {
     expect(getRollingMetricDirection(300, 600)).toBe("up");
     expect(getRollingMetricDirection(600, 300)).toBe("down");
@@ -227,6 +232,10 @@ describe("Download-Gesamtgröße", () => {
 });
 
 describe("verbleibendes Downloadvolumen", () => {
+  it("shows a fourth TB decimal so fast downloads stay visibly responsive", () => {
+    expect(formatRemainingDownloadBytes({ bytes: Math.round(1.125 * 1024 ** 4), unknownItems: 0 })).toBe("1.1250 TB");
+  });
+
   it("summiert nur offene bekannte Restbytes und klemmt überladene Fortschritte bei null", () => {
     const items = [
       item("partial", "remaining", "downloading", { downloadedBytes: 750_000_000, totalBytes: 2_000_000_000 }),