diff --git a/tests/browser/workspace-inspect.spec.mjs b/tests/browser/workspace-inspect.spec.mjs
index 698cd3d0..3d77f112 100644
--- a/tests/browser/workspace-inspect.spec.mjs
+++ b/tests/browser/workspace-inspect.spec.mjs
@@ -290,6 +290,29 @@ test('D155: an unreadable file stays on the page with its alert', async ({ page
     await expect(viewer(page)).toHaveCount(0);
 });
 
+test('D155: an AVI keeps its note and toast and does not open the viewer', async ({ page }) => {
+    await openInspect(page);
+    // AVI and WMV metadata is never read and the browser cannot play them, so the page keeps the selection's note.
+    const avi = { name: 'clip.avi', mimeType: 'video/x-msvideo', buffer: Buffer.concat([Buffer.from('RIFF'), Buffer.alloc(4), Buffer.from('AVI LIST'), Buffer.alloc(64)]) };
+    await choose(page, avi);
+    await expect(page.locator('#workspace-toast')).toHaveText(TOAST);
+    await expect(action(page)).toHaveAttribute('aria-disabled', 'false');
+    await expect(viewer(page)).toHaveCount(0);
+    await reopenViewer(page);
+    await expect(viewer(page).locator('#viewer-title')).toHaveText('clip.avi');
+});
+
+test('D155: a selection that lands while another dialog is open leaves the viewer closed', async ({ page }) => {
+    await openInspect(page);
+    await page.evaluate(() => { const other = document.createElement('dialog'); other.id = 'other-dialog'; other.textContent = 'Other'; document.body.append(other); other.showModal(); });
+    await choose(page, parityPng('f02.png'));
+    await expect(action(page)).toHaveAttribute('aria-disabled', 'false');
+    await expect(viewer(page)).toHaveCount(0);
+    await page.evaluate(() => document.querySelector('#other-dialog').close());
+    await reopenViewer(page);
+    await expect(viewer(page).locator('#viewer-title')).toHaveText('f02.png');
+});
+
 test('D155: at 390px the opened details are reachable below the media', async ({ page }) => {
     await page.setViewportSize({ width: 390, height: 844 });
     await openInspect(page);
diff --git a/web/js/workspace/inspect.mjs b/web/js/workspace/inspect.mjs
index 6c0ca899..ee67d7ec 100644
--- a/web/js/workspace/inspect.mjs
+++ b/web/js/workspace/inspect.mjs
@@ -280,11 +280,12 @@ export function mountInspect(main, { parentScope, api, sender }) {
     /** Runs `run` after this task, or once `preview`'s video stops starting (metadata, an error, or the D62 limit). */
     function whenSettled(preview, run) {
         if (!preview || !isStarting(preview.node)) { queueMicrotask(run); return; }
+        // `run` checks that the page and the selection are still current, so the page's end may call `done` too.
         const settled = new AbortController();
-        const done = () => { settled.abort(); clearTimeout(timer); if (!scope.signal.aborted) run(); };
+        const done = () => { settled.abort(); clearTimeout(timer); run(); };
         const timer = setTimeout(done, STARTING_VIDEO_MS);
         for (const type of ['loadedmetadata', 'error']) preview.node.addEventListener(type, done, { once: true, signal: settled.signal });
-        scope.signal.addEventListener('abort', () => { settled.abort(); clearTimeout(timer); }, { once: true, signal: settled.signal });
+        scope.cleanup(done);
     }
     /** The viewer on the current selection, details showing (D155 amends D97); focus returns to `trigger` on close. */
     function openViewer(trigger) {