diff --git a/tests/browser/workflows.spec.mjs b/tests/browser/workflows.spec.mjs
index 453a3ac..ab5d842 100644
--- a/tests/browser/workflows.spec.mjs
+++ b/tests/browser/workflows.spec.mjs
@@ -64,11 +64,16 @@ test('actual Tags page reloads the selected filter and opens its image viewer',
     await page.goto('/prompt_manager/admin#/tags');
     await page.locator('[data-tag-name="cats"]').click();
     await expect(page.locator('#tagPromptsGrid')).toContainText('Cat portrait');
+    const dogs = page.waitForResponse(response => response.url().includes('/tags/dogs/prompts?'));
     await page.locator('[data-tag-name="dogs"]').click();
+    const [shown] = (await (await dogs).json()).prompts[0].images;
     await expect(page.locator('#tagPromptsGrid')).toContainText('Dog landscape');
     await expect(page.locator('#tagPromptsGrid')).not.toContainText('Cat portrait');
     await page.locator('#tagPromptsGrid img').first().click();
     await expect(page.locator('.viewer-canvas img')).toBeVisible();
+    // The viewer's title names the shown image through the page's title callback. ViewerJS renders it only once the
+    // image is viewed, so closing at "visible" alone left the callback unrun on slower hosts (CI coverage missed it).
+    await expect(page.locator('.viewer-title')).toHaveText(shown.filename);
     await page.locator('.viewer-container').getByRole('button', { name: 'Close', exact: true }).click();
     await expect(page.locator('.viewer-container')).toHaveCount(0);
 });
diff --git a/tests/browser/workspace-library.spec.mjs b/tests/browser/workspace-library.spec.mjs
index 0b35746..1b830dd 100644
--- a/tests/browser/workspace-library.spec.mjs
+++ b/tests/browser/workspace-library.spec.mjs
@@ -25,6 +25,8 @@ async function loadShelfPages(page,more,pages) {
         await more.evaluate(node=>node.click());await response;await expect(more).toHaveAttribute('aria-disabled','false');
     }
 }
+/** Resolves in the rendering frame after every frame callback the page had already queued (callbacks run in request order). */
+const nextFrame=page=>page.evaluate(()=>new Promise(resolve=>requestAnimationFrame(()=>resolve())));
 async function openHistory(page,text='Cat portrait') {
     await cards(page).filter({has:page.getByText(text,{exact:true})}).getByRole('button',{name:'Explore history',exact:true}).click();
     await expect(history(page)).toBeVisible();
@@ -103,7 +105,8 @@ test('library infinite loading keeps unique parents and keyboard-accessible hist
         const appended=await (await nextPage).json();expect(appended.items.length).toBeGreaterThan(0);hasMore=appended.has_more;
         if(hasMore)await expect(more).toHaveAttribute('aria-disabled','false');
     }
-    await expect(more).toBeHidden();expect(await cards(page).count()).toBeLessThan(80);
+    // The last page's render queued the window update for the next frame; count after that frame, not before it.
+    await expect(more).toBeHidden();await nextFrame(page);expect(await cards(page).count()).toBeLessThan(80);
     const ids=await cards(page).evaluateAll(nodes=>nodes.map(node=>node.dataset.promptId));expect(new Set(ids).size).toBe(ids.length);
     await expect(page.getByRole('button',{name:/next page|previous page/i})).toHaveCount(0);
     const firstId=await cards(page).first().getAttribute('data-prompt-id');
@@ -376,14 +379,16 @@ async function observeLibrary(page, hold=false) {
             holdFrames(){holdingFrames=true;},
             releaseFrames(){holdingFrames=false;const callbacks=[...heldFrames.values()];heldFrames.clear();for(const callback of callbacks)callback();},
             equal(){for(const record of records){const entries=[...record.latest.values()].filter(entry=>record.targets.has(entry.target));if(entries.length)record.callback(entries,record.native);}},
+            // Resolves once two consecutive rendering frames find no Library frame queued. Each check runs inside a native
+            // frame callback, so a frame the page queues later in that update (a scroll event, a ResizeObserver delivery) is
+            // still pending there. A timer is not a frame: under CPU load a 60 ms wait could end before the scroll's frame.
+            settled(){return new Promise(resolve=>{let quiet=0;const check=()=>{quiet=pending.size?0:quiet+1;if(quiet>=2)resolve();else raf(check);};raf(check);});},
             stats(){return {requested,pending:pending.size,heldFrames:heldFrames.size,measurements:records.reduce((sum,record)=>sum+record.entries.size,0),mutations,unmounted,targets:records.reduce((sum,record)=>sum+record.targets.size,0)};},
         };
     },{hold});
 }
 async function settleLibrary(page) {
-    await expect.poll(async()=>page.evaluate(()=>window.libraryObservation.stats().pending)).toBe(0);
-    await page.evaluate(()=>new Promise(resolve=>setTimeout(resolve,60)));
-    await expect.poll(async()=>page.evaluate(()=>window.libraryObservation.stats().pending)).toBe(0);
+    await page.evaluate(()=>window.libraryObservation.settled());
 }
 async function firstVisibleParent(page) {
     return cards(page).evaluateAll(nodes=>{