fix(zoom): auto-placed zoom regions follow the cursor for their whole span

src/components/video-editor/VideoEditor.tsx

@@ -1136,6 +1136,11 @@ export default function VideoEditor() {
 
 	// Builds fresh "auto" zoom regions from cursor telemetry without overlapping
 	// existing ones. Used by both the on-load auto-suggest pass and the wand toggle.
+	// These regions always follow the cursor for their whole span (focusMode "auto") —
+	// that's the entire point of an auto-placed zoom: it should pan to track the cursor
+	// as it moves, not freeze at the dwell point that triggered the suggestion. This is
+	// independent of the global "Auto Focus All" toggle, which only affects the default
+	// for manually-drawn zoom regions.
 	const buildAutoZoomRegions = useCallback(
 		(existingRegions: ZoomRegion[]): ZoomRegion[] => {
 			const totalMs = Math.round(duration * 1000);
@@ -1152,11 +1157,11 @@ export default function VideoEditor() {
 				depth: DEFAULT_ZOOM_DEPTH,
 				customScale: ZOOM_DEPTH_SCALES[DEFAULT_ZOOM_DEPTH],
 				focus: clampFocusToDepth(suggestion.focus, DEFAULT_ZOOM_DEPTH),
-				focusMode: autoFocusAll ? ("auto" as const) : undefined,
+				focusMode: "auto" as const,
 				source: "auto" as const,
 			}));
 		},
-		[cursorTelemetry, duration, autoFocusAll],
+		[cursorTelemetry, duration],
 	);
 
 	// Auto-suggest zooms once per fresh recording (no existing zooms, telemetry

src/components/video-editor/videoPlayback/zoomRegionUtils.test.ts

@@ -0,0 +1,59 @@
+import { describe, expect, it } from "vitest";
+import type { CursorTelemetryPoint, ZoomRegion } from "../types";
+import { DEFAULT_ZOOM_DEPTH, ZOOM_DEPTH_SCALES } from "../types";
+import { findDominantRegion } from "./zoomRegionUtils";
+
+/**
+ * Regression coverage for issue #72: an auto-placed zoom region must pan to follow
+ * the cursor for its whole span, not freeze at the focus point captured when the
+ * region was created/suggested.
+ */
+describe("findDominantRegion — auto-zoom cursor following", () => {
+	const baseRegion: ZoomRegion = {
+		id: "zoom-1",
+		startMs: 0,
+		endMs: 4000,
+		depth: DEFAULT_ZOOM_DEPTH,
+		customScale: ZOOM_DEPTH_SCALES[DEFAULT_ZOOM_DEPTH],
+		// The static focus captured at suggestion time (e.g. the dwell centroid) — should
+		// be ignored in favor of the live cursor position once focusMode is "auto". Kept
+		// within the depth-3 focus bounds (~0.28-0.72) so clamping doesn't distort assertions.
+		focus: { cx: 0.35, cy: 0.5 },
+		focusMode: "auto",
+		source: "auto",
+	};
+
+	// Cursor sweeps steadily from the left edge to the right edge across the region.
+	const movingTelemetry: CursorTelemetryPoint[] = [
+		{ timeMs: 0, cx: 0.1, cy: 0.5 },
+		{ timeMs: 2000, cx: 0.5, cy: 0.5 },
+		{ timeMs: 4000, cx: 0.9, cy: 0.5 },
+	];
+
+	it("tracks the cursor across the region instead of freezing at the initial focus", () => {
+		const early = findDominantRegion([baseRegion], 200, { cursorTelemetry: movingTelemetry });
+		const mid = findDominantRegion([baseRegion], 2000, { cursorTelemetry: movingTelemetry });
+		const late = findDominantRegion([baseRegion], 3800, { cursorTelemetry: movingTelemetry });
+
+		expect(early.region).not.toBeNull();
+		expect(mid.region).not.toBeNull();
+		expect(late.region).not.toBeNull();
+
+		// The focus must move meaningfully between samples (cursor-following), not stay pinned.
+		expect(mid.region?.focus.cx).toBeGreaterThan(early.region?.focus.cx ?? 0);
+		expect(late.region?.focus.cx).toBeGreaterThan(mid.region?.focus.cx ?? 0);
+
+		// And it must not equal the static creation-time focus baked into the region.
+		expect(mid.region?.focus.cx).not.toBeCloseTo(baseRegion.focus.cx, 2);
+	});
+
+	it("stays frozen at the static focus when focusMode is not auto (manual regions unaffected)", () => {
+		const manualRegion: ZoomRegion = { ...baseRegion, focusMode: "manual", source: "manual" };
+
+		const early = findDominantRegion([manualRegion], 200, { cursorTelemetry: movingTelemetry });
+		const late = findDominantRegion([manualRegion], 3800, { cursorTelemetry: movingTelemetry });
+
+		expect(early.region?.focus.cx).toBeCloseTo(manualRegion.focus.cx, 5);
+		expect(late.region?.focus.cx).toBeCloseTo(manualRegion.focus.cx, 5);
+	});
+});