diff --git a/TESTING.md b/TESTING.md
index f04f7094..3f9f3b36 100644
--- a/TESTING.md
+++ b/TESTING.md
@@ -2928,6 +2928,34 @@ concept's danger "Archive…" maps to "Archive variant…" followed by a "Delete
 Tests: `tests/browser/workspace-library-delete.spec.mjs` (#481 cases), and `workspace-library-editor.spec.mjs` (the
 hand-off and the comparisons) and `library-editor-visual.spec.mjs` with the renamed button. JS only: no restart.
 
+### Delete review and prompt-page polish (#512)
+
+Found in the live test of #505/#507/#509. **D163** (beyond the concept, maintainer ruling 2026-10-29: delete was hard to
+find on a prompt's page): the prompt page heading ends with a **"⋯" More menu** button after Send to ComfyUI
+(`more-menu.mjs`: `aria-haspopup="menu"`, `aria-expanded`; Enter, Space or ArrowDown opens it on its first item, ArrowUp
+on its last; arrows, Home and End move; Escape closes it and returns focus to ⋯; Tab, an outside press or a choice
+closes it). It holds one danger item, "Delete prompt…", which opens the same review as Edit metadata's Delete prompt…
+(D161, kept) and returns focus to ⋯. The menu uses the concept's button, surface, border and toast shadow, opens
+right-aligned under ⋯, and opens rightwards where the heading wraps it to the left edge (390px). It is held with Edit
+metadata while the page's review or write runs, and disabled on a gone prompt's page.
+
+Also:
+- The Delete… review leaves out rows with nothing in them ("Delete permanently: 0 …", "Archive: 0 …"), close-only
+  reviews included.
+- A review opened from a prompt's page is titled "Delete this prompt" or "Archive this prompt" (following the choice),
+  and its close-only sentence reads "This prompt cannot be deleted or archived."
+- An archived prompt that is another prompt's negative is named so: "1 prompt used as another prompt's negative:
+  hidden, restorable" (or "N prompts in a saved pair (M used as another prompt's negative)"), with the sentence that its
+  variant stays.
+- A prompt page whose prompt no longer exists (404, after a delete or from a stale link) reads "This prompt no longer
+  exists. It may have been deleted." with "Open the Prompt library", no Retry; Edit metadata and ⋯ are disabled.
+- Item 5 of #512 does not fail on the code after #505: the archived shelf's button reads "← Prompt library", and under a
+  remembered search the heading's count equals what the archived shelf lists. A regression test pins both.
+
+Tests: `tests/js/workspace-library-delete.test.js` (#512) and `tests/browser/workspace-library-delete.spec.mjs` (#512
+cases: the menu by mouse, keyboard and at 390px, the gone page, the titles, the count under a search). JS only: no
+restart.
+
 ### No 1–5 prompt rating in the workspace (#447)
 
 **D153** (maintainer ruling 2026-10-28: the star is only for favorites; the concept keeps
diff --git a/tests/browser/concept-inventory.mjs b/tests/browser/concept-inventory.mjs
index 9234a50d..19edf093 100644
--- a/tests/browser/concept-inventory.mjs
+++ b/tests/browser/concept-inventory.mjs
@@ -421,7 +421,8 @@ export function measureInventory(scope) {
             description:when(description,()=>({className:description.className,text:description.textContent,...font(description),...edges(description)})),
             actions:when(actions,()=>({...layout(actions),...edges(actions),
                 fullWidth:px(rect(actions).width)===px(rect(heading).width),stacked:copy?rect(actions).top>=rect(copy).bottom-0.5:null,
-                buttons:[...actions.querySelectorAll('button')].map(node=>({text:node.textContent.trim(),primary:node.classList.contains('ca-primary'),
+                // D163: a closed menu's items are not heading actions.
+                buttons:[...actions.querySelectorAll('button')].filter(node=>!node.closest('[role="menu"]')).map(node=>({text:node.textContent.trim(),primary:node.classList.contains('ca-primary'),
                     ...font(node),...edges(node),minHeight:getComputedStyle(node).minHeight,height:px(rect(node).height)}))}))};
     }
     // ---- Images (#249 C7). Every box is relative to its section, every section to `main` (vertical rhythm). ----
diff --git a/tests/browser/history-concept.spec.mjs b/tests/browser/history-concept.spec.mjs
index b58499e1..ffd96385 100644
--- a/tests/browser/history-concept.spec.mjs
+++ b/tests/browser/history-concept.spec.mjs
@@ -26,7 +26,8 @@ const SECTIONS=['heading','history','noPageScroll'];
  */
 export function mapHistoryConcept(reference) {
     const {history}=reference.oracle;
-    return {...reference,history:{...history,
+    // D163 (#512): the heading as laid out with the More menu button (the oracle's heading).
+    return {...reference,heading:reference.oracle.heading,history:{...history,
         // D24: "N tracked runs" is the recorded window's `recorded_run_count`; the fixture records one run per image, so
         // the concept's "4 tracked runs" holds by construction (asserted on both documents below).
         summary:history.summary,
@@ -120,11 +121,14 @@ async function conceptAsRecorded(page) {
         const add=[...document.querySelectorAll('.timeline-panel .row-actions > button')].find(node=>node.textContent==='+ Add negative');
         const archived=add.cloneNode(false);archived.removeAttribute('data-action');archived.removeAttribute('data-prompt');
         archived.setAttribute('aria-pressed','false');archived.textContent=label;add.after(archived);
-        window.__historyOracle={timeline,order:[...lanes].reverse(),texts,archived};
+        // D163 (#512): the heading ends with the "⋯" More menu button, drawn as the concept's Edit metadata button.
+        const edit=[...document.querySelectorAll('#main > .heading .heading-actions > button')].find(node=>node.textContent.trim()==='Edit metadata');
+        const moreButton=edit.cloneNode(false);moreButton.removeAttribute('data-action');moreButton.textContent='⋯';edit.parentElement.append(moreButton);
+        window.__historyOracle={timeline,order:[...lanes].reverse(),texts,archived,moreButton};
     },SHOW_ARCHIVED);
     await settle(page);
     return ()=>page.evaluate(()=>{
-        const {timeline,order,texts,archived}=window.__historyOracle;
+        const {timeline,order,texts,archived,moreButton}=window.__historyOracle;moreButton.remove();
         order.forEach((lane,index)=>{lane.style.setProperty('--lane-offset',`${38+index*47}px`);timeline.append(lane);});
         for(const [span,text] of texts)span.textContent=text;
         archived.remove();delete window.__historyOracle;
diff --git a/tests/browser/workspace-library-delete.spec.mjs b/tests/browser/workspace-library-delete.spec.mjs
index 36ca84a4..d18d8ac8 100644
--- a/tests/browser/workspace-library-delete.spec.mjs
+++ b/tests/browser/workspace-library-delete.spec.mjs
@@ -50,7 +50,8 @@ test('Delete… reviews the selection, deletes the unpaired, archives the paired
     await expect(review(page)).toHaveAccessibleName('Delete or archive selected prompts');
     const grid=review(page).locator('dl.meta-grid > div');
     await expect(grid.locator('dt')).toHaveText(['Delete permanently','Archive','Protected (kept)','Image links removed','Backup']);
-    await expect(grid.locator('dd')).toHaveText(['1 prompt not in a saved pair','1 prompt in a saved pair: hidden, restorable',
+    // #512: Cat portrait is also another prompt's negative in the fixture, so the review says so.
+    await expect(grid.locator('dd')).toHaveText(['1 prompt not in a saved pair',"1 prompt used as another prompt's negative: hidden, restorable",
         '1: Library extra 0000','0 images will no longer show these prompts (files stay on disk)','Create and verify before deleting']);
     await expect(review(page).locator('p.small')).toHaveCount(3);
     await expect(review(page).getByRole('button',{name:'Delete 1 and archive 1 prompt',exact:true})).toHaveClass(/danger/);
@@ -81,7 +82,7 @@ test('Show archived prompts lists archived prompts, and Restore on its bar retur
     await openReview(page);
     await expect(review(page)).toHaveAccessibleName('Archive selected prompts');
     // The archive reason is the saved pair, for one or many prompts (live note on #470): never negative variants.
-    await expect(review(page).locator('dl.meta-grid > div').filter({hasText:'Archive'}).locator('dd')).toHaveText('2 prompts in a saved pair: hidden, restorable');
+    await expect(review(page).locator('dl.meta-grid > div').filter({hasText:'Archive'}).locator('dd')).toHaveText("2 prompts in a saved pair (1 used as another prompt's negative): hidden, restorable");
     await review(page).getByRole('button',{name:'Archive 2 prompts',exact:true}).click();
     await expect(toast(page)).toHaveText('Archived 2 prompts.');
     await expect(cards(page)).toHaveCount(before.length-2);
@@ -300,7 +301,8 @@ test('the page\'s delete holds one review at a time, Escape returns focus, and a
     await review(page).getByRole('button',{name:'Archive 1 prompt',exact:true}).click();
     await expect(page.locator('.library-archived-notice')).toBeVisible();
     await editMetadata(page).click();await editor(page).getByRole('button',{name:'Delete prompt…',exact:true}).click();
-    await expect(review(page).locator('p.small').last()).toHaveText('None of the selected prompts can be deleted or archived.');
+    // #512: the page's review names its one prompt.
+    await expect(review(page).locator('p.small').last()).toHaveText('This prompt cannot be deleted or archived.');
     await expect(review(page).getByRole('button',{name:/^(Delete|Archive)/})).toHaveCount(0);
 });
 
@@ -459,3 +461,94 @@ test('a failed review keeps the selection, and a selection nothing can change op
     await expect(bar(page).getByRole('button',{name:'Delete…',exact:true})).not.toHaveAttribute('aria-disabled','true');
     expect(byText(await items(request),'Library extra 0000')).toBeDefined();
 });
+
+// #512 (live test of #505/#507/#509): the prompt page's "⋯" More menu (D163), a gone prompt's page, single-prompt titles.
+const more=page=>page.locator('#workspace-main .heading-actions').getByRole('button',{name:'More actions for this prompt',exact:true});
+const moreMenu=page=>page.getByRole('menu',{name:'More actions for this prompt'});
+test('the prompt page\'s More menu opens Delete prompt…, by mouse and keyboard, and closes on Escape or outside (#512 D163)',async({page,request})=>{
+    const dual=byText(await items(request),'Dual role portrait');
+    await page.goto(`/prompt_manager/workspace#/library/${dual.id}`);
+    const heading=page.locator('#workspace-main .heading-actions > button, #workspace-main .heading-actions > .more-menu > button');
+    await expect(heading).toHaveText(['← Prompt library','Edit metadata','Send to ComfyUI','⋯']);
+    await expect(more(page)).toHaveAttribute('aria-haspopup','menu');await expect(more(page)).toHaveAttribute('aria-expanded','false');
+    await expect(moreMenu(page)).toBeHidden();
+    // Keyboard: Enter opens on the first item; Escape closes and returns focus.
+    await more(page).focus();await page.keyboard.press('Enter');
+    await expect(more(page)).toHaveAttribute('aria-expanded','true');
+    const item=moreMenu(page).getByRole('menuitem',{name:'Delete prompt…',exact:true});
+    await expect(item).toBeFocused();await expect(item).toHaveClass(/\bdanger\b/);
+    await page.keyboard.press('ArrowDown');await expect(item).toBeFocused();
+    await page.keyboard.press('Escape');
+    await expect(moreMenu(page)).toBeHidden();await expect(more(page)).toBeFocused();await expect(more(page)).toHaveAttribute('aria-expanded','false');
+    // ArrowUp opens on the last item; ArrowUp, Home and End move within it (one item here); Tab closes it.
+    await page.keyboard.press('ArrowUp');await expect(item).toBeFocused();
+    for(const key of ['ArrowUp','Home','End']) {await page.keyboard.press(key);await expect(item).toBeFocused();}
+    await page.keyboard.press('Tab');await expect(moreMenu(page)).toBeHidden();await expect(more(page)).toHaveAttribute('aria-expanded','false');
+    // Space opens too; an outside press closes it.
+    await more(page).focus();await page.keyboard.press(' ');await expect(item).toBeFocused();
+    await page.locator('#workspace-main h1').click();await expect(moreMenu(page)).toBeHidden();
+    // Choosing it opens the page's review, titled for this prompt; Cancel returns focus to ⋯.
+    await more(page).click();await item.click();
+    await expect(moreMenu(page)).toBeHidden();
+    await expect(review(page)).toHaveAccessibleName('Archive this prompt');
+    await expect(choice(page).getByRole('radio',{name:'Archive (hidden, restorable)'})).toBeChecked();
+    await choice(page).getByRole('radio',{name:'Delete permanently, with their saved pairs'}).check();
+    await expect(review(page).locator('#modal-title')).toHaveText('Delete this prompt');
+    await review(page).getByRole('button',{name:'Cancel',exact:true}).click();
+    await expect(review(page)).toHaveCount(0);await expect(more(page)).toBeFocused();
+    expect(byText(await items(request),'Dual role portrait')?.id).toBe(dual.id);
+});
+
+test('the More menu fits a 390px viewport and works by touch (#512 D163)',async({page,request})=>{
+    const dual=byText(await items(request),'Dual role portrait');
+    await page.setViewportSize({width:390,height:844});
+    await page.goto(`/prompt_manager/workspace#/library/${dual.id}`);
+    await more(page).click();
+    const item=moreMenu(page).getByRole('menuitem',{name:'Delete prompt…',exact:true});
+    await expect(item).toBeVisible();
+    const box=await moreMenu(page).boundingBox();
+    expect(box.x).toBeGreaterThanOrEqual(0);expect(box.x+box.width).toBeLessThanOrEqual(390);
+    await item.click();
+    await review(page).getByRole('button',{name:'Archive 1 prompt',exact:true}).click();
+    await expect(toast(page)).toHaveText('Archived 1 prompt.');
+    await expect(page.locator('.library-archived-notice')).toBeVisible();
+});
+
+test('a deleted prompt\'s page says it no longer exists, with the way back and no Retry (#512)',async({page,request})=>{
+    const dual=byText(await items(request),'Dual role portrait');
+    await deleteFromPage(page,dual.id);
+    await expect(review(page)).toHaveAccessibleName('Archive this prompt');
+    await choice(page).getByRole('radio',{name:'Delete permanently, with their saved pairs'}).check();
+    await review(page).getByRole('button',{name:'Delete 1 prompt',exact:true}).click();
+    await expect(page).toHaveURL(/#\/library$/);
+    await page.goto(`/prompt_manager/workspace#/library/${dual.id}`);
+    await expect(page.locator('#workspace-main .library-status')).toHaveText('This prompt no longer exists. It may have been deleted.');
+    await expect(page.getByRole('button',{name:'Retry prompt history'})).toHaveCount(0);
+    await expect(editMetadata(page)).toBeDisabled();await expect(more(page)).toBeDisabled();
+    await page.getByRole('button',{name:'Open the Prompt library',exact:true}).click();
+    await expect(page).toHaveURL(/#\/library$/);
+});
+
+test('the archived shelf\'s heading count and its list agree under a remembered search (#512 item 5)',async({page,request})=>{
+    const all=await items(request);
+    const dual=byText(all,'Dual role portrait'),dog=byText(all,'Dog landscape');
+    await archiveByApi(request,[dual.id]);
+    await page.goto(route);
+    // A search that matches a shelf prompt but not the archived one.
+    await page.getByRole('searchbox').fill('landscape');
+    await expect(card(page,dog.id)).toHaveCount(1);await expect(card(page,dual.id)).toHaveCount(0);
+    const matching=(await(await request.get('/prompt_manager/library?limit=100&shelf=archived&text=landscape')).json()).items.length;
+    await expect(showArchived(page)).toHaveText(`Show archived prompts (${matching})`);
+    // Leave and come back: the remembered search is shown and still counts the same.
+    await page.goto('/prompt_manager/workspace#/overview');await page.goto(route);
+    await expect(page.getByRole('searchbox')).toHaveValue('landscape');
+    await expect(showArchived(page)).toHaveText(`Show archived prompts (${matching})`);
+    await showArchived(page).click();
+    await expect(backToLibrary(page)).toBeVisible();
+    if(matching) await expect(cards(page)).toHaveCount(matching);
+    else await expect(page.locator('.library-status')).toHaveText('No archived prompts match.');
+    await page.getByRole('searchbox').fill('');
+    await expect(card(page,dual.id)).toHaveCount(1);
+    await backToLibrary(page).click();
+    await expect(showArchived(page)).toHaveText('Show archived prompts (1)');
+});
diff --git a/tests/browser/workspace-library-editor.spec.mjs b/tests/browser/workspace-library-editor.spec.mjs
index 0d4018dd..cc858a0a 100644
--- a/tests/browser/workspace-library-editor.spec.mjs
+++ b/tests/browser/workspace-library-editor.spec.mjs
@@ -540,8 +540,9 @@ test('new from Images cancel preserves browse',async({page})=>{
 
 test('history heading follows the concept and sends the selected saved pair',async({page})=>{
     const f=page.fixture;await openHistory(page,f.positive_id);
-    const actions=headingActions(page).locator('button');
-    expect(await visibleNames(actions)).toEqual(['← Prompt library','Edit metadata','Send to ComfyUI']);
+    const actions=headingActions(page).locator('button:not([role="menuitem"])');
+    // D163 (#512): the More menu button follows Send to ComfyUI.
+    expect(await visibleNames(actions)).toEqual(['← Prompt library','Edit metadata','Send to ComfyUI','⋯']);
     await expect(page.getByRole('link',{name:'Back to library',exact:true})).toHaveCount(0);
     const send=actions.nth(2);await expect(send).toHaveClass(/\bsend\b/);await expect(send.locator('svg')).toHaveCount(1);
     await expect(send).toHaveAccessibleName(`Send prompt pair to ComfyUI: ${f.metadata.title}`);
diff --git a/tests/js/workspace-library-delete.test.js b/tests/js/workspace-library-delete.test.js
index 991cead6..58cc0a3b 100644
--- a/tests/js/workspace-library-delete.test.js
+++ b/tests/js/workspace-library-delete.test.js
@@ -42,8 +42,13 @@ test('the grid shows each row only when it applies, with protected titles in sel
         ['Image links removed', '3 images will no longer show these prompts (files stay on disk)'],
         ['Backup', 'Create and verify before deleting'],
     ]);
+    // #512: a row with nothing in it is left out.
     const archiveOnly = reviewOf(preview({archive: [2]}));
-    assert.deepEqual(reviewGrid(archiveOnly).map(([term]) => term), ['Delete permanently', 'Archive']);
+    assert.deepEqual(reviewGrid(archiveOnly).map(([term]) => term), ['Archive']);
+    const deleteOnly = reviewOf(preview({delete: [1]}));
+    assert.deepEqual(reviewGrid(deleteOnly).map(([term]) => term), ['Delete permanently', 'Image links removed', 'Backup']);
+    const keptOnly = reviewOf(preview({protected: [7]}));
+    assert.deepEqual(reviewGrid(keptOnly, id => names[id]), [['Protected (kept)', '1: Seven']]);
     const off = reviewOf(preview({delete: [1], backup: 'off'}));
     assert.equal(reviewGrid(off).at(-1)[1], 'Off: no safety backup (System › Backup & export › Recovery policy)');
 });
@@ -136,7 +141,7 @@ test('reviewOf keeps only well-formed ids and counts from an answer', async () =
         not_found: 'x', image_links: 2, backup: 'maybe', not_archived: -3});
     assert.deepEqual(review, {shelf: 'active', notArchived: 0, epoch: null, delete: [1, 2], archive: [], protected: [], alreadyArchived: 0, notFound: 0,
         imageLinks: 2, backup: 'on', disk: null, deletable: [], digests: {},
-        pairedCounts: {pairs: 0, archivedPairs: 0, variants: 0, keptNegatives: 0}, pairedImageLinks: 0, choice: 'archive'});
+        pairedCounts: {pairs: 0, archivedPairs: 0, variants: 0, keptNegatives: 0}, pairedImageLinks: 0, choice: 'archive', archiveOnly: []});
 });
 
 test('the archived notice says why (the saved pair) and names negative variants only when there are any', async () => {
@@ -291,3 +296,32 @@ test('the outcome names prompts restored since the review', async () => {
     assert.equal(none.toast, 'Nothing was deleted. 1 was restored since the review and kept. 1 changed since the review and ' +
         'was not deleted. The Library was reloaded.');
 });
+
+// #512 (live test of #505/#507/#509): the review names a single prompt, and a negative selected without its positive.
+test('a review from a prompt\'s own page names that prompt', async () => {
+    const {reviewOf, reviewTitle, blockedReason} = await source;
+    const single = review => ({...review, single: true});
+    assert.equal(reviewTitle(single(reviewOf(preview({delete: [1]})))), 'Delete this prompt');
+    assert.equal(reviewTitle(single(reviewOf(preview({archive: [2]})))), 'Archive this prompt');
+    const kept = single(reviewOf(preview({protected: [3]})));
+    assert.equal(reviewTitle(kept), 'Delete this prompt');
+    assert.equal(blockedReason(kept), 'This prompt cannot be deleted or archived.');
+    assert.equal(reviewTitle(single(reviewOf(preview({archive: [2], deletable: [2], review_digests: {2: 'c'.repeat(64)}}),
+        'archived'))), 'Delete this prompt');
+});
+
+test('a negative used by another prompt is named as such when it is archived', async () => {
+    const {reviewOf, reviewGrid, reviewSentences} = await source;
+    const negative = reviewOf(preview({archive: [5], deletable: []}));
+    assert.deepEqual(reviewGrid(negative), [['Archive', "1 prompt used as another prompt's negative: hidden, restorable"]]);
+    assert.deepEqual(reviewSentences(negative), ["Prompts used as another prompt's negative are archived instead of deleted, so " +
+        "that prompt's variant stays. To bring them back, press Show archived prompts, select them and press Restore."]);
+    const mixed = reviewOf(preview({archive: [2, 5], deletable: [2], review_digests: {2: 'c'.repeat(64)}}));
+    assert.deepEqual(reviewGrid(mixed)[0], ['Archive', "2 prompts in a saved pair (1 used as another prompt's negative): hidden, restorable"]);
+    // A paired prompt whose review digest is missing is not called another prompt's negative (review M1).
+    const noDigest = reviewOf(preview({archive: [2], deletable: [2], review_digests: {}}));
+    assert.deepEqual(reviewGrid(noDigest), [['Archive', '1 prompt in a saved pair: hidden, restorable']]);
+    const sentences = reviewSentences(mixed);
+    assert.match(sentences[0], /^Prompts in a saved pair, as its positive or its negative, are archived instead of deleted/);
+    assert.match(sentences[1], /^Prompts used as another prompt's negative are archived instead of deleted, so that prompt's variant stays\.$/);
+});
diff --git a/tools/vendor/frontend-coverage-baseline.json b/tools/vendor/frontend-coverage-baseline.json
index 8da3fe11..33a431e5 100644
--- a/tools/vendor/frontend-coverage-baseline.json
+++ b/tools/vendor/frontend-coverage-baseline.json
@@ -491,6 +491,12 @@
     "functions": 98,
     "statements": 98
   },
+  "workspace/more-menu.mjs": {
+    "lines": 80,
+    "branches": 70,
+    "functions": 80,
+    "statements": 80
+  },
   "workspace/plural.mjs": {
     "lines": 98,
     "branches": 98,
diff --git a/web/js/workspace/library-delete.mjs b/web/js/workspace/library-delete.mjs
index b658152d..1146f26a 100644
--- a/web/js/workspace/library-delete.mjs
+++ b/web/js/workspace/library-delete.mjs
@@ -26,6 +26,7 @@ export const COPY = Object.freeze({
     nothing: `${NOTHING} The Library was reloaded.`,
     none: 'None of the selected prompts can be deleted or archived.',
     noneArchived: 'None of the selected prompts can be deleted.',
+    noneSingle: 'This prompt cannot be deleted or archived.',
     restoreStorage: 'The library was restored or moved since this page loaded. No prompt was returned to the Library.',
     restoreUnconfirmed: 'Returning the prompts could not be confirmed. The Library was reloaded.',
     restoreFailed: 'The prompts could not be returned to the Library. Try again.',
@@ -65,6 +66,10 @@ function pairedOf(preview) {
         pairedCounts: { pairs: count(counts.pairs), archivedPairs: count(counts.archived_pairs),
             variants: count(counts.variants), keptNegatives: count(counts.kept_negatives) },
         pairedImageLinks: count(preview?.paired_image_links), choice: 'archive',
+        // #512: archive ids the server says cannot be deleted (another prompt's negative); none from an older answer.
+        // The server's own list, not the digest-checked one: a deletable prompt with a bad digest is still paired.
+        archiveOnly: Array.isArray(preview?.deletable)
+            ? [...archive].filter(id => !ids(preview.deletable).includes(id)) : [],
     };
 }
 
@@ -87,6 +92,8 @@ function plan(review) {
 
 export function reviewTitle(review) {
     const { plain, paired, archive } = plan(review), deletes = plain.length + paired.length;
+    // #512: a review opened from a prompt's own page names that prompt.
+    if (review.single) return deletes || !archive.length ? 'Delete this prompt' : 'Archive this prompt';
     if (onArchivedShelf(review)) return 'Delete archived prompts';
     if (!archive.length) return 'Delete selected prompts';
     if (!deletes) return 'Archive selected prompts';
@@ -112,16 +119,23 @@ export function archivedNoticeText(variantCount) {
 /** The review's `[term, value]` rows (design §7.2); rows that do not apply are left out. */
 export function reviewGrid(review, titleOf = () => null) {
     if (permanent(review)) return permanentGrid(review, titleOf);
-    const rows = [
-        ['Delete permanently', `${countOf(review.delete.length, 'prompt')} not in a saved pair`],
-        // The archive reason is the saved pair (a pair's positive or negative), with or without negative variants.
-        ['Archive', `${countOf(review.archive.length, 'prompt')} in a saved pair: hidden, restorable`],
-    ];
+    // #512: rows with nothing in them are left out.
+    const rows = [];
+    if (review.delete.length) rows.push(['Delete permanently', `${countOf(review.delete.length, 'prompt')} not in a saved pair`]);
+    if (review.archive.length) rows.push(['Archive', archiveValue(review)]);
     keptRows(rows, review, titleOf);
     if (review.delete.length) deleteRows(rows, review, review.imageLinks);
     return rows;
 }
 
+/** The archive reason is the saved pair (a pair's positive or negative); #512 names another prompt's negative. */
+function archiveValue(review) {
+    const total = review.archive.length, negatives = review.archiveOnly.length;
+    if (negatives === total) return `${countOf(total, 'prompt')} used as another prompt's negative: hidden, restorable`;
+    const detail = negatives ? ` (${negatives.toLocaleString('en-US')} used as another prompt's negative)` : '';
+    return `${countOf(total, 'prompt')} in a saved pair${detail}: hidden, restorable`;
+}
+
 function keptRows(rows, review, titleOf) {
     if (review.protected.length) {
         const names = protectedNames(review, titleOf);
@@ -163,12 +177,17 @@ function permanentGrid(review, titleOf) {
 /** The review's sentences, in order, each when it applies. */
 export function reviewSentences(review) {
     if (permanent(review)) return permanentSentences(review);
-    const sentences = [];
-    if (review.archive.length) {
+    const sentences = [], negatives = review.archiveOnly.length;
+    if (review.archive.length > negatives) {
         sentences.push('Prompts in a saved pair, as its positive or its negative, are archived instead of deleted, so the ' +
             'pair and its runs stay intact. To delete them later or bring them back, press Show archived prompts, select them ' +
             'and press Delete… or Restore.');
     }
+    // #512: a negative selected without its positive stays the other prompt's variant.
+    if (negatives) {
+        sentences.push("Prompts used as another prompt's negative are archived instead of deleted, so that prompt's variant " +
+            `stays.${negatives === review.archive.length ? ' To bring them back, press Show archived prompts, select them and press Restore.' : ''}`);
+    }
     if (review.delete.length) sentences.push(removeSentence(review));
     if (review.protected.length) sentences.push(PROTECTED_SENTENCE);
     return sentences;
@@ -210,8 +229,9 @@ export function primaryLabel(review) {
 
 /** Why a review cannot start, or null: nothing to change, or no room for the promised backup. */
 export function blockedReason(review) {
-    if (onArchivedShelf(review) && !review.delete.length && !review.deletable.length) return COPY.noneArchived;
-    if (!review.delete.length && !review.archive.length) return COPY.none;
+    const none = review.single ? COPY.noneSingle : null;
+    if (onArchivedShelf(review) && !review.delete.length && !review.deletable.length) return none ?? COPY.noneArchived;
+    if (!review.delete.length && !review.archive.length) return none ?? COPY.none;
     const deletes = review.delete.length + plan(review).paired.length;
     if (deletes && review.disk && review.disk.sufficient === false) {
         return typeof review.disk.message === 'string' && review.disk.message
@@ -372,7 +392,8 @@ export async function reviewPromptDelete({ api, scope, trigger, ids: promptIds,
     }
     if (scope.signal.aborted) return;
     if (failure !== null || !preview?.success) { onSettled(previewOutcome(failure), null, failure); return; }
-    const review = { ...reviewOf(preview), epoch };
+    // #512: the review names this one prompt.
+    const review = { ...reviewOf(preview), epoch, single: true };
     openDeleteReview({ scope, trigger, review, titleOf, onDismiss,
         onStart: async chosen => {
             let result = null, error = null;
diff --git a/web/js/workspace/library.mjs b/web/js/workspace/library.mjs
index f9190deb..4b221ca1 100644
--- a/web/js/workspace/library.mjs
+++ b/web/js/workspace/library.mjs
@@ -18,8 +18,11 @@ import {openRefineDialog,openContentDialog} from './workspace-dialogs.mjs';
 import {mountLibrarySelection} from './library-selection.mjs';
 import {fallBackToOriginal,replaceOnError,showsThumbnail,thumbnailSource} from './thumbnail-support.mjs';
 import {COPY as DELETE_COPY,RESTORE_URL,archivedNoticeText,restoreOutcome,reviewPromptDelete} from './library-delete.mjs';
+import {createMoreMenu} from './more-menu.mjs';
 
 let shelfVisit=null;
+// #512: what a prompt page says when its prompt no longer exists (404).
+const PROMPT_GONE='This prompt no longer exists. It may have been deleted.';
 // Every confirmed receipt advances this; a shelf mounted before it never restores its cached stream.
 let writeGeneration=0, focusHeadingOnMount=false, savedParentId=null;
 // The pair one reconciled save names, taken once by the history it opens (the concept selects it after a save, app.js 986).
@@ -488,7 +491,11 @@ export function mountLibrary(main,api,parentScope,{positiveId,savedState=null,on
         headingDescription(main,history,'Prompt history · one positive, one shared gallery');
         const actions=headingActions(main,history);
         const back=createButton('← Prompt library'),edit=createButton('Edit metadata'),send=createButton('','send');
-        send.append(createWorkspaceIcon('send'),el('span','Send to ComfyUI'));send.disabled=true;actions.append(back,edit,send);
+        send.append(createWorkspaceIcon('send'),el('span','Send to ComfyUI'));send.disabled=true;
+        // D163 (#512, maintainer 2026-10-29): a "⋯" More menu after Send to ComfyUI holds Delete prompt…, so delete is
+        // findable on the page; Edit metadata keeps its own Delete prompt… (D161).
+        const moreMenu=createMoreMenu({scope,label:'More actions for this prompt',items:[{label:'Delete prompt…',danger:true,onSelect:()=>deletePrompt(moreMenu.button)}]});
+        actions.append(back,edit,send,moreMenu.element);
         let blocks,galleryScope,detail,contentScope,updateBranches,updateParent,current=null;
         scope.cleanup(()=>{blocks?.dispose();galleryScope?.dispose();contentScope?.dispose();});
         // Every visit opens on the first negative, as the concept's navigate() does (app.js 1149: state.variant = 0);
@@ -504,14 +511,16 @@ export function mountLibrary(main,api,parentScope,{positiveId,savedState=null,on
         // can race the delete; aria-disabled keeps it focusable for the return.
         function holdEdit(held) {
             deleting=held;
-            if(held) edit.setAttribute('aria-disabled','true');else edit.removeAttribute('aria-disabled');
+            for(const button of [edit,moreMenu.button]) {
+                if(held) button.setAttribute('aria-disabled','true');else button.removeAttribute('aria-disabled');
+            }
         }
-        function deletePrompt() {
+        function deletePrompt(trigger=edit) {
             const shown=detail;if(deleting || !shown?.positive) return;
             // One review at a time, as the selection bar holds itself (a second press during the preview starts nothing).
             holdEdit(true);
-            reviewPromptDelete({api,scope,trigger:edit,ids:[shown.positive.id],epoch:shown.library_epoch,
-                titleOf:()=>displayTitle(shown.positive),onDismiss:()=>{holdEdit(false);if(edit.isConnected) edit.focus({preventScroll:true});},
+            reviewPromptDelete({api,scope,trigger,ids:[shown.positive.id],epoch:shown.library_epoch,
+                titleOf:()=>displayTitle(shown.positive),onDismiss:()=>{holdEdit(false);if(trigger.isConnected) trigger.focus({preventScroll:true});},
                 onSettled:(outcome,result,failure)=>{
                     holdEdit(false);
                     if(outcome.committed) invalidateLibraryAfterWrite({kind:'bulk-delete',receipt:result ?? {phase:'unconfirmed'}});
@@ -571,6 +580,17 @@ export function mountLibrary(main,api,parentScope,{positiveId,savedState=null,on
             if(detail && state.detail && !state.loading && !state.error) {detail=state.detail;updateParent();updateBranches(state);return;}
             contentScope?.dispose();contentScope=createScope();detail=null;updateBranches=null;updateParent=null;current=null;send.disabled=true;
             blocks?.dispose();blocks=null;galleryScope?.dispose();galleryScope=null;body.replaceChildren();
+            // #512: a prompt that no longer exists (deleted, or a stale link) says so, with the way back; no Retry.
+            // Edit metadata and ⋯ act on a loaded prompt only (review M2).
+            const hadFocus=[edit,moreMenu.button].includes(document.activeElement);
+            const loaded=!state.loading && !state.error;edit.disabled=!loaded;moreMenu.setDisabled(!loaded);
+            if(state.error?.status===404) {
+                const message=el('p',PROMPT_GONE,'library-status');message.setAttribute('role','status');body.append(message);
+                const open=createButton('Open the Prompt library');contentScope.listen(open,'click',()=>{window.location.hash='#/library';});body.append(open);
+                // A focused control that was just disabled hands focus to the way back (review M3).
+                if(hadFocus) open.focus({preventScroll:true});
+                return;
+            }
             if(state.loading || state.error) {
                 const message=el('p',state.loading?'Loading prompt history…':'Prompt history could not be loaded.','library-status');message.setAttribute('role',state.error?'alert':'status');body.append(message);
                 if(state.error) {const retry=createButton('Retry prompt history');contentScope.listen(retry,'click',()=>loader.load(positiveId));body.append(retry);}return;
diff --git a/web/js/workspace/more-menu.mjs b/web/js/workspace/more-menu.mjs
new file mode 100644
index 00000000..664cf7ec
--- /dev/null
+++ b/web/js/workspace/more-menu.mjs
@@ -0,0 +1,85 @@
+import { createButton } from '../shared/toolkit/core.js';
+
+/**
+ * A "⋯" (More) menu button for a page heading (D163, #512; the concept has no menu, so it uses the concept's button
+ * and surface styles). The button carries `aria-haspopup="menu"` and `aria-expanded`; Enter, Space or ArrowDown opens
+ * the menu on its first item, ArrowUp on its last; ArrowUp/ArrowDown/Home/End move between items; Escape closes it and
+ * returns focus to the button; Tab, an outside pointer press or choosing an item closes it. A held button
+ * (`aria-disabled`) or a disabled one opens nothing. Listeners live on `scope`.
+ *
+ * `items`: `[{ label, danger, onSelect }]`. Returns `{ element, button, setDisabled(disabled) }`.
+ */
+let menus = 0;
+export function createMoreMenu({ scope, label, items }) {
+    const id = `more-menu-${++menus}`;
+    const element = document.createElement('div');
+    element.className = 'more-menu';
+    const button = createButton('⋯');
+    button.classList.add('more-menu-button');
+    button.setAttribute('aria-label', label);
+    button.setAttribute('aria-haspopup', 'menu');
+    button.setAttribute('aria-expanded', 'false');
+    button.setAttribute('aria-controls', id);
+    const menu = document.createElement('div');
+    menu.className = 'more-menu-list';
+    menu.id = id;
+    menu.setAttribute('role', 'menu');
+    menu.setAttribute('aria-label', label);
+    menu.hidden = true;
+    const entries = items.map(item => {
+        const entry = createButton(item.label, item.danger ? 'danger' : '');
+        entry.setAttribute('role', 'menuitem');
+        entry.tabIndex = -1;
+        scope.listen(entry, 'click', () => { close(false); item.onSelect(); });
+        return entry;
+    });
+    menu.append(...entries);
+    element.append(button, menu);
+
+    const isOpen = () => !menu.hidden;
+    const held = () => button.disabled || button.getAttribute('aria-disabled') === 'true';
+    function open(index) {
+        if (held()) return;
+        menu.hidden = false;
+        // Right-aligned under the button; where the heading wraps it to the left edge (390px), it opens rightwards.
+        menu.style.left = menu.style.right = '';
+        if (menu.getBoundingClientRect().left < 0) Object.assign(menu.style, { left: '0', right: 'auto' });
+        button.setAttribute('aria-expanded', 'true');
+        entries.at(index)?.focus();
+    }
+    function close(refocus) {
+        if (!isOpen()) return;
+        menu.hidden = true;
+        button.setAttribute('aria-expanded', 'false');
+        if (refocus) button.focus();
+    }
+    function move(step) {
+        const at = entries.indexOf(document.activeElement);
+        entries[(at + step + entries.length) % entries.length].focus();
+    }
+    scope.listen(button, 'click', () => (isOpen() ? close(true) : open(0)));
+    scope.listen(button, 'keydown', event => {
+        if (event.key !== 'ArrowDown' && event.key !== 'ArrowUp') return;
+        event.preventDefault();
+        open(event.key === 'ArrowDown' ? 0 : -1);
+    });
+    scope.listen(menu, 'keydown', event => {
+        const keys = { ArrowDown: () => move(1), ArrowUp: () => move(-1), Home: () => entries[0].focus(),
+            End: () => entries.at(-1).focus(), Escape: () => close(true) };
+        if (event.key === 'Tab') { close(false); return; }
+        if (!keys[event.key]) return;
+        event.preventDefault();
+        keys[event.key]();
+    });
+    // Focus leaving the menu (a screen reader's cursor, a script) closes it too.
+    scope.listen(element, 'focusout', event => { if (event.relatedTarget && !element.contains(event.relatedTarget)) close(false); });
+    // An outside press closes it; capture, so a press that a page control stops still counts.
+    const outside = event => { if (isOpen() && !element.contains(event.target)) close(false); };
+    document.addEventListener('pointerdown', outside, true);
+    scope.cleanup(() => document.removeEventListener('pointerdown', outside, true));
+    return {
+        element,
+        button,
+        setDisabled(disabled) { button.disabled = disabled; if (disabled) close(false); },
+    };
+}
diff --git a/web/js/workspace/workspace.css b/web/js/workspace/workspace.css
index b421d847..c602f8b5 100644
--- a/web/js/workspace/workspace.css
+++ b/web/js/workspace/workspace.css
@@ -482,3 +482,14 @@ pre.prompt-text { font: inherit; font-size: 12px; line-height: 1.75; margin-bloc
 .tagging-modal .tag-action-notice { flex: 1 0 100%; display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 8px; margin: 0; color: var(--ca-text); font-size: 12px; /* D147 */ }
 .tagging-modal .tag-action-notice > span { flex: 1 1 16em; }
 .tag-image-preview.tag-preview-empty { display: grid; place-items: center; padding: 8px; text-align: center; font-size: 12px; color: var(--ca-muted); background: var(--ca-field); box-sizing: border-box; /* D147 */ }
+
+/* D163 (#512): the prompt page's "⋯" More menu. The concept has no menu; it uses the concept's button, surface, border
+   and toast shadow, opens under its button, right-aligned so it stays inside a 390px viewport. */
+.more-menu { position: relative; display: inline-flex; }
+.more-menu-list {
+    position: absolute; top: calc(100% + 6px); right: 0; z-index: 20; display: flex; flex-direction: column; gap: 4px;
+    min-width: 160px; padding: 6px; background: var(--ca-surface); border: 1px solid var(--ca-border); border-radius: 6px;
+    box-shadow: 0 8px 35px #0004;
+}
+.more-menu-list[hidden] { display: none; }
+.more-menu-list > button { justify-content: flex-start; text-align: left; width: 100%; white-space: nowrap; }