diff --git a/server/src/nest/assistant/assistant-tool-offer.ts b/server/src/nest/assistant/assistant-tool-offer.ts
index 76c3f645c..98ab26557 100644
--- a/server/src/nest/assistant/assistant-tool-offer.ts
+++ b/server/src/nest/assistant/assistant-tool-offer.ts
@@ -178,13 +178,20 @@ export function isOfferedInJourney(name: string, className: string | undefined):
   return isStudioController(className) || (className !== undefined && JOURNEY_READ_CONTROLLERS.has(className));
 }
 
+/**
+ * The controllers whose reads work only for someone who may change the book:
+ * a design draft is its editor's, so a viewer's design_book, revise_book_design
+ * and get_book_design could only refuse.
+ */
+const EDITOR_READ_CONTROLLERS: ReadonlySet<string> = new Set(['JourneyBookDesignMcp']);
+
 /**
  * Whether a Studio conversation keeps an attached tool once its schema and
  * annotations are known. Only tools that work on the conversation's journey
  * (they take the `journeyId` the server pins) stay, so the conversation never
- * reaches another journey; of those every read, and the book's writes only
- * for someone who may change the book. The journey's own writes (entries,
- * photos, its trips) stay with the journey page.
+ * reaches another journey; of those every read but the design draft's, which,
+ * like the book's writes, go only to someone who may change the book. The
+ * journey's own writes (entries, photos, its trips) stay with the journey page.
  */
 export function keptInJourney(
   className: string | undefined,
@@ -193,7 +200,7 @@ export function keptInJourney(
   canWrite: boolean,
 ): boolean {
   if (!pinned) return false;
-  if (kind === 'read') return true;
+  if (kind === 'read') return canWrite || className === undefined || !EDITOR_READ_CONTROLLERS.has(className);
   return canWrite && isStudioController(className);
 }
 
diff --git a/server/src/nest/journey/journey-book-design.service.ts b/server/src/nest/journey/journey-book-design.service.ts
index faec906f0..1c236bcb7 100644
--- a/server/src/nest/journey/journey-book-design.service.ts
+++ b/server/src/nest/journey/journey-book-design.service.ts
@@ -204,6 +204,8 @@ export class JourneyBookDesignService {
    * is and is named under `skipped`; nothing applied is a 409.
    */
   async apply(journeyId: number, userId: number, args: ApplyBookDesignRequest): Promise<BookDesignApplyResult> {
+    // The rights come before the draft: a viewer or an outsider holds none, and is told 403 or 404, not 410.
+    await this.requireEditor(journeyId, userId);
     const draft = await this.draftOf(userId, journeyId, args.designId);
     const { record, result, revisionId } = await this.books.editBook(
       journeyId,
diff --git a/server/src/nest/photos/photo-colour-signals.ts b/server/src/nest/photos/photo-colour-signals.ts
index f849cc6f1..a5d4420b0 100644
--- a/server/src/nest/photos/photo-colour-signals.ts
+++ b/server/src/nest/photos/photo-colour-signals.ts
@@ -50,7 +50,7 @@ function samples(data: Uint8Array, total: number): Rgb[] {
   const out: Rgb[] = [];
   for (let i = 0; i < total; i += stride) {
     const o = i * 4;
-    out.push([data[o] ?? 0, data[o + 1] ?? 0, data[o + 2] ?? 0]);
+    out.push([data[o], data[o + 1], data[o + 2]]);
   }
   return out;
 }
@@ -98,21 +98,20 @@ export function paletteOf(data: Uint8Array, width: number, height: number): stri
     for (const colour of pixels) {
       const at = nearest(centres, colour);
       const sum = sums[at];
-      if (!sum) continue;
       sum[0] += colour[0];
       sum[1] += colour[1];
       sum[2] += colour[2];
-      members[at] = (members[at] ?? 0) + 1;
+      members[at] += 1;
     }
     // The last round only counts: the centres stay where the counting found them.
     if (round === ROUNDS) break;
     sums.forEach((sum, i) => {
-      const n = members[i] ?? 0;
+      const n = members[i];
       if (n > 0) centres[i] = [sum[0] / n, sum[1] / n, sum[2] / n];
     });
   }
   return centres
-    .map((centre, i) => ({ centre, share: (members[i] ?? 0) / pixels.length, i }))
+    .map((centre, i) => ({ centre, share: members[i] / pixels.length, i }))
     .filter((c) => c.share >= MIN_SHARE)
     .sort((a, b) => b.share - a.share || a.i - b.i)
     .map((c) => `#${hex2(c.centre[0])}${hex2(c.centre[1])}${hex2(c.centre[2])}:${c.share.toFixed(2)}`);
@@ -127,9 +126,9 @@ export function edgeSignals(data: Uint8Array, width: number, height: number): Om
   const grey = new Float32Array(width * height);
   for (let i = 0; i < grey.length; i++) {
     const o = i * 4;
-    grey[i] = 0.299 * (data[o] ?? 0) + 0.587 * (data[o + 1] ?? 0) + 0.114 * (data[o + 2] ?? 0);
+    grey[i] = 0.299 * data[o] + 0.587 * data[o + 1] + 0.114 * data[o + 2];
   }
-  const at = (k: number) => grey[k] ?? 0;
+  const at = (k: number) => grey[k];
   const sums = new Array<number>(GRID * GRID).fill(0);
   const counts = new Array<number>(GRID * GRID).fill(0);
   let energy = 0;
@@ -141,8 +140,8 @@ export function edgeSignals(data: Uint8Array, width: number, height: number): Om
       const i = row * width + col;
       const lap = Math.abs(at(i - 1) + at(i + 1) + at(i - width) + at(i + width) - 4 * at(i));
       const cell = cellRow * GRID + Math.min(GRID - 1, Math.floor((col * GRID) / width));
-      sums[cell] = (sums[cell] ?? 0) + lap;
-      counts[cell] = (counts[cell] ?? 0) + 1;
+      sums[cell] += lap;
+      counts[cell] += 1;
       energy += lap;
       sx += lap * ((col + 0.5) / width);
       sy += lap * ((row + 0.5) / height);
@@ -150,7 +149,7 @@ export function edgeSignals(data: Uint8Array, width: number, height: number): Om
   }
   const busy = sums
     .map((sum, cell) => {
-      const n = counts[cell] ?? 0;
+      const n = counts[cell];
       const level = n > 0 ? Math.min(15, Math.round(sum / n / BUSY_STEP)) : 0;
       return level.toString(16);
     })
diff --git a/server/src/nest/photos/photo-signals-runner.ts b/server/src/nest/photos/photo-signals-runner.ts
index de924259f..a5a69787f 100644
--- a/server/src/nest/photos/photo-signals-runner.ts
+++ b/server/src/nest/photos/photo-signals-runner.ts
@@ -105,7 +105,7 @@ function greyStats(data: Uint8Array, width: number, height: number) {
   let clipped = 0;
   for (let i = 0; i < total; i++) {
     const o = i * 4;
-    const y = 0.299 * (data[o] ?? 0) + 0.587 * (data[o + 1] ?? 0) + 0.114 * (data[o + 2] ?? 0);
+    const y = 0.299 * data[o] + 0.587 * data[o + 1] + 0.114 * data[o + 2];
     grey[i] = y;
     sum += y;
     if (y <= CLIP_LOW || y >= CLIP_HIGH) clipped++;
@@ -114,7 +114,7 @@ function greyStats(data: Uint8Array, width: number, height: number) {
   let n = 0;
   let mean = 0;
   let m2 = 0;
-  const at = (k: number) => grey[k] ?? 0;
+  const at = (k: number) => grey[k];
   for (let row = 1; row < height - 1; row++) {
     for (let col = 1; col < width - 1; col++) {
       const i = row * width + col;
diff --git a/server/tests/unit/nest/assistant/assistant-journey-session.test.ts b/server/tests/unit/nest/assistant/assistant-journey-session.test.ts
index e97075285..fcf224770 100644
--- a/server/tests/unit/nest/assistant/assistant-journey-session.test.ts
+++ b/server/tests/unit/nest/assistant/assistant-journey-session.test.ts
@@ -72,7 +72,7 @@ describe('a Studio tool session', () => {
     }
   });
 
-  it('ASTJSES-002: a viewer is offered the reads and not one write', async () => {
+  it('ASTJSES-002: a viewer is offered the reads but the design draft tools, and not one write', async () => {
     const { journeyId } = await ownerWithJourneys();
     const { user: viewer } = await makeUser(orm);
     await addJourneyContributor(orm, journeyId, viewer.id, 'viewer');
@@ -81,6 +81,11 @@ describe('a Studio tool session', () => {
       const names = session.specs().map((spec) => spec.name);
       expect(names).toEqual(expect.arrayContaining(['get_book', 'describe_book_page', 'list_journey_entries']));
       for (const name of [...BOOK_WRITES, 'set_book_cover']) expect(names, name).not.toContain(name);
+      const listed = registry.list().map((entry) => entry.name);
+      for (const name of ['design_book', 'get_book_design', 'revise_book_design']) {
+        expect(listed, name).toContain(name);
+        expect(names, name).not.toContain(name);
+      }
       for (const name of names) expect(session.kindOf(name), name).toBe('read');
     } finally {
       await session.close();
diff --git a/server/tests/unit/nest/journey/book-design-apply.test.ts b/server/tests/unit/nest/journey/book-design-apply.test.ts
index 5207aafe8..8ae500c5c 100644
--- a/server/tests/unit/nest/journey/book-design-apply.test.ts
+++ b/server/tests/unit/nest/journey/book-design-apply.test.ts
@@ -6,14 +6,19 @@
  * untouched; a page whose photos left the gallery stays out; the draft's
  * format and title come along unless someone set others since, and a page
  * size moved since takes nothing. A journey that had no book gets the chosen
- * pages as a new book (a cover photo gone since leaves an empty frame), one
- * that lost its book since, or got one since, gets nothing.
+ * pages as a new book (a cover photo gone since leaves an empty frame, a map
+ * stop's picture gone since leaves a dot), one that lost its book since, or
+ * got one since, gets nothing. A plan row the draft holds no page for writes
+ * nothing, and a book at the page limit takes no new page.
  */
 import { applyDesignDraft, type DraftToApply } from '../../../../src/nest/journey/book-design-apply';
 import {
   blankBook,
+  bookMapElementSchema,
   bookPageSetupForPreset,
   bookPhotoElementSchema,
+  bookShapeElementSchema,
+  MAX_SPREADS,
   type BookDesignPlanRow,
   type BookDocument,
   type BookSpread,
@@ -243,4 +248,75 @@ describe('applyDesignDraft', () => {
     };
     expect(applyDesignDraft(reordered, draft, new Set([4])).applied).toEqual(['a']);
   });
+
+  it('JBAPPLY-011: a new book empties only the gone pictures on its cover, a map stop among them', () => {
+    const point = (photoId: number | null) => ({ lat: 38.7, lng: -9.1, label: '', photoId });
+    const map = bookMapElementSchema.parse({
+      id: 'm-c',
+      kind: 'map',
+      frame: { x: 0, y: 0, w: 40, h: 40 },
+      points: [point(5), point(6), point(null)],
+    });
+    const empty = bookPhotoElementSchema.parse({ id: 'p-c-e', kind: 'photo', frame: { x: 0, y: 0, w: 20, h: 20 } });
+    const shape = bookShapeElementSchema.parse({ id: 's-c', kind: 'shape', frame: { x: 0, y: 0, w: 10, h: 10 } });
+    const framed = page('c', 'cover', [6]);
+    const cover = { ...framed, elements: [...framed.elements, empty, map, shape] };
+    const doc = book([cover, ...pages('f:first', 'l:last', 'k:back')]);
+    const plan = doc.spreads.map((s) => row(s.id, 'insert'));
+    const draft: DraftToApply = { base: null, doc, plan, selection: [] };
+
+    const out = applyDesignDraft(null, draft, new Set([6]));
+
+    const [frame, blank, stops, rest] = out.doc.spreads[0]?.elements ?? [];
+    expect(frame).toMatchObject({ kind: 'photo', photoId: 6 });
+    expect(blank).toMatchObject({ kind: 'photo', photoId: null });
+    expect(stops?.kind === 'map' ? stops.points.map((p) => p.photoId) : 'not a map').toEqual([null, 6, null]);
+    expect(rest).toEqual(shape);
+    expect(out.applied).toEqual(['c', 'f', 'l', 'k']);
+  });
+
+  it('JBAPPLY-012: a new page with only a dropped page and a page the book lacks before it follows the cover', () => {
+    const base = book(pages('c:cover', 'a', 'k:back'));
+    const draft: DraftToApply = {
+      base,
+      doc: book(pages('c:cover', 'm', 'n', 'k:back')),
+      plan: [row('x', 'drop'), row('m', 'insert'), row('n', 'insert')],
+      selection: ['n'],
+    };
+
+    const out = applyDesignDraft(base, draft, new Set());
+
+    expect(out.doc.spreads.map((s) => s.id)).toEqual(['c', 'n', 'a', 'k']);
+    expect(out.applied).toEqual(['n']);
+    expect(out.skipped).toEqual([
+      { spreadId: 'x', reason: 'excluded' },
+      { spreadId: 'm', reason: 'excluded' },
+    ]);
+  });
+
+  it('JBAPPLY-013: a plan row whose page the draft does not hold changes nothing and is not named', () => {
+    const base = stored();
+    const draft: DraftToApply = {
+      base,
+      doc: book(pages('c:cover')),
+      plan: [row('a', 'replace'), row('n', 'insert')],
+      selection: ['a', 'n'],
+    };
+
+    const out = applyDesignDraft(base, draft, new Set());
+
+    expect([out.applied, out.skipped]).toEqual([[], []]);
+    expect(out.doc.spreads).toEqual(base.spreads);
+  });
+
+  it('JBAPPLY-014: a book at the page limit takes no new page, the page named as changed since', () => {
+    const inner = Array.from({ length: MAX_SPREADS - 1 }, (_, i) => page(`i${i}`, 'inner'));
+    const full = book([page('c', 'cover'), ...inner]);
+    const draft: DraftToApply = { base: full, doc: book(pages('n')), plan: [row('n', 'insert')], selection: ['n'] };
+
+    const out = applyDesignDraft(full, draft, new Set());
+
+    expect(out.skipped).toEqual([{ spreadId: 'n', reason: 'changed_since' }]);
+    expect(out.doc.spreads).toHaveLength(MAX_SPREADS);
+  });
 });
diff --git a/server/tests/unit/nest/journey/journey-book-design.mcp.test.ts b/server/tests/unit/nest/journey/journey-book-design.mcp.test.ts
index 7f638d06f..c956c7b9c 100644
--- a/server/tests/unit/nest/journey/journey-book-design.mcp.test.ts
+++ b/server/tests/unit/nest/journey/journey-book-design.mcp.test.ts
@@ -7,9 +7,10 @@
  * journey group, the design, its read and its revision as reads, the apply,
  * the undo targets and the book-level changes as writes; the tools answer
  * what the services answer, so an editor designs, revises and applies, a
- * viewer is refused and an outsider told the journey is not there; the apply
- * tells every member once, the asking one included; describe_book_page reads
- * a draft page by its designId.
+ * viewer is refused every change and an outsider told the journey is not
+ * there by every tool, before a draft is looked for (403 or 404, not 410);
+ * the apply tells every member once, the asking one included;
+ * describe_book_page reads a draft page by its designId.
  */
 import { JourneyEntryPhotos } from '../../../../src/db/entities/JourneyEntryPhotos.entity';
 import { JourneyPhotos } from '../../../../src/db/entities/JourneyPhotos.entity';
@@ -194,4 +195,37 @@ describe('the design tools', () => {
     const restored = bookWriteResultSchema.parse(answered(await books.restoreBookLayout(back, ctx(owner.id))));
     expect(restored.version).toBe(removed.version + 1);
   });
+
+  it('JBDMCP-005: the other tools refuse an outsider, and a viewer every change, before a draft is read', async () => {
+    const { journey, viewer, stranger } = await crew();
+    const draft = { journeyId: journey.id, designId: 'd-none' };
+    const revise = { ...draft, spreadId: 'sp-none', ops: [{ op: 'background' as const, color: '#f4efe6' }] };
+    const revision = { journeyId: journey.id, revisionId: 1, expectedVersion: 1 };
+    const page = { journeyId: journey.id, spreadId: 'sp-none' };
+    const removal = { journeyId: journey.id, layoutId: 'l-none', expectedVersion: 1 };
+    const putBack = { journeyId: journey.id, layout: '{}', expectedVersion: 1 };
+    const format = { journeyId: journey.id, preset: 'a4-portrait' as const };
+    const gone = 'Journey not found';
+
+    await expect(designs.getBookDesign(draft, ctx(stranger.id))).rejects.toThrow(gone);
+    await expect(designs.reviseBookDesign(revise, ctx(stranger.id))).rejects.toThrow(gone);
+    await expect(designs.applyBookDesign(draft, ctx(stranger.id))).rejects.toThrow(gone);
+    await expect(designs.restoreBookRevision(revision, ctx(stranger.id))).rejects.toThrow(gone);
+    await expect(books.duplicateBookPage(page, ctx(stranger.id))).rejects.toThrow(gone);
+    await expect(books.saveBookLayout(page, ctx(stranger.id))).rejects.toThrow(gone);
+    await expect(books.removeBookLayout(removal, ctx(stranger.id))).rejects.toThrow(gone);
+    await expect(books.restoreBookLayout(putBack, ctx(stranger.id))).rejects.toThrow(gone);
+    await expect(books.setBookSetup(format, ctx(stranger.id))).rejects.toThrow(gone);
+
+    // A viewer may read the book, so a draft it never made is gone; every change is refused.
+    await expect(designs.getBookDesign(draft, ctx(viewer.id))).rejects.toThrow('This design is no longer kept');
+    await expect(designs.reviseBookDesign(revise, ctx(viewer.id))).rejects.toThrow('Not allowed');
+    await expect(designs.applyBookDesign(draft, ctx(viewer.id))).rejects.toThrow('Not allowed');
+    await expect(designs.restoreBookRevision(revision, ctx(viewer.id))).rejects.toThrow('Not allowed');
+    await expect(books.duplicateBookPage(page, ctx(viewer.id))).rejects.toThrow('Not allowed');
+    await expect(books.saveBookLayout(page, ctx(viewer.id))).rejects.toThrow('Not allowed');
+    await expect(books.removeBookLayout(removal, ctx(viewer.id))).rejects.toThrow('Not allowed');
+    await expect(books.restoreBookLayout(putBack, ctx(viewer.id))).rejects.toThrow('Not allowed');
+    expect(t.realtime.broadcastToUserMock).not.toHaveBeenCalled();
+  });
 });
diff --git a/server/tests/unit/nest/journey/journey-book-design.service.test.ts b/server/tests/unit/nest/journey/journey-book-design.service.test.ts
index d6e09342b..be98bf8bf 100644
--- a/server/tests/unit/nest/journey/journey-book-design.service.test.ts
+++ b/server/tests/unit/nest/journey/journey-book-design.service.test.ts
@@ -3,18 +3,19 @@
  * the shared engine. Taken from JourneyBookDesignModule over a snapshot test
  * db, with the realtime fake and the photo bytes stubbed (nothing to measure).
  *
- * What it pins: a design is a draft, nothing written or sent, made by the
- * owner and editors only (a viewer 403, an outsider 404) and read back by its
- * maker only (410 for anyone else and once it is gone); a revision of a draft
- * page is checked like an edit and changes only the draft, a kept page it
- * revises is proposed; the selection names only pages the plan changes; the
- * apply writes the chosen pages in one version with one announcement, keeps
- * the book as it was as a revision in the same transaction, names the pages
- * left out and the ones changed since, refuses when nothing is left (409,
- * nothing written) and at a stale version, and forgets the draft; a journey
- * without a book gets a new one and no revision; restoring the revision puts
- * the book back only at the version the apply left, and never writes a revision that
- * does not read back; five revisions are kept.
+ * What it pins: a design is a draft, nothing written or sent, made and
+ * applied by the owner and editors only (a viewer 403, an outsider 404, before
+ * any draft is looked for) and read back by its maker only (410 for anyone
+ * else and once it is gone); a revision of a draft page is checked like an
+ * edit and changes only the draft, a kept page it revises is proposed; the
+ * selection names only pages the plan changes; the apply writes the chosen
+ * pages in one version with one announcement, keeps the book as it was as a
+ * revision in the same transaction, names the pages left out and the ones
+ * changed since, refuses when nothing is left (409, nothing written) and at a
+ * stale version, and forgets the draft; a journey without a book gets a new
+ * one and no revision; restoring the revision puts the book back only at the
+ * version the apply left, and never writes a revision that does not read
+ * back; five revisions are kept.
  */
 import { JourneyBookRevisions } from '../../../../src/db/entities/JourneyBookRevisions.entity';
 import { JourneyEntryPhotos } from '../../../../src/db/entities/JourneyEntryPhotos.entity';
@@ -144,7 +145,7 @@ describe('a design draft', () => {
     expect(await designs.describeDraft(journey.id, editor.id, answer.design_id)).toEqual(answer);
   });
 
-  it("JBDSN-002: only the owner and editors design; a draft is its maker's alone and gone for anyone else", async () => {
+  it("JBDSN-002: only the owner and editors design or apply; a draft is its maker's alone, gone for others", async () => {
     const { journey, owner, viewer, stranger } = await crew();
     expect(await refusal(() => designs.design(journey.id, viewer.id))).toEqual({ status: 403, code: 'book_read_only' });
     expect(await refusal(() => designs.design(journey.id, stranger.id))).toMatchObject({ status: 404 });
@@ -158,6 +159,13 @@ describe('a design draft', () => {
     expect(await refusal(() => designs.describeDraft(journey.id, owner.id, 'd-none'))).toEqual(gone);
     expect(await refusal(() => designs.draftView(journey.id, stranger.id, id))).toMatchObject({ status: 404 });
     expect(await refusal(() => designs.select(journey.id, viewer.id, id, []))).toMatchObject({ status: 403 });
+    // Taking the owner's draft is a question of rights first, never answered as a design gone.
+    const taking = { designId: id };
+    expect(await refusal(() => designs.apply(journey.id, viewer.id, taking))).toEqual({
+      status: 403,
+      code: 'book_read_only',
+    });
+    expect(await refusal(() => designs.apply(journey.id, stranger.id, taking))).toMatchObject({ status: 404 });
   });
 
   it('JBDSN-003: a revision changes a page of the draft like an edit would, nothing of the book; a kept page revised is proposed', async () => {
diff --git a/server/tests/unit/nest/photos/photo-colour-signals.test.ts b/server/tests/unit/nest/photos/photo-colour-signals.test.ts
index c01f3d486..07b068c2d 100644
--- a/server/tests/unit/nest/photos/photo-colour-signals.test.ts
+++ b/server/tests/unit/nest/photos/photo-colour-signals.test.ts
@@ -2,8 +2,10 @@
  * The colour signals of a photo (PHSIG3-*), on pixels drawn here: a picture
  * half flat and half textured has its busy cells and its salient point on
  * the textured side, a two-colour picture has both colours in its palette
- * with their shares, a flat one has one colour, no salient point and a calm
- * grid; the measurement of a whole photo carries them, at version 3.
+ * with their shares (two equal ones always in the same order), a flat one has
+ * one colour, no salient point and a calm grid, the smallest picture is busy
+ * only around its one inner pixel; the measurement of a whole photo carries
+ * them, at version 3.
  */
 import { colourSignals, edgeSignals, paletteOf } from '../../../../src/nest/photos/photo-colour-signals';
 import { measurePhoto, PHOTO_SIGNALS_ALGO } from '../../../../src/nest/photos/photo-signals-runner';
@@ -75,4 +77,18 @@ describe('colour signals', () => {
     expect(measured?.busy).toMatch(/^[0-9a-f]{64}$/);
     expect(measured?.salX).toBeGreaterThan(0.6);
   });
+
+  it('PHSIG3-005: on the smallest picture only the cell holding the one inner pixel can be busy', () => {
+    const dot = edgeSignals(
+      pixels(3, 3, (x, y) => (x === 1 && y === 1 ? [255, 255, 255] : [0, 0, 0])),
+      3,
+      3,
+    );
+    expect(dot).toEqual({ busy: `${'0'.repeat(18)}f${'0'.repeat(45)}`, salX: 0.5, salY: 0.5 });
+  });
+
+  it('PHSIG3-006: two colours of equal share come out in one order every time, the lower histogram bin first', () => {
+    const halves = pixels(100, 100, (x) => (x < 50 ? [200, 30, 30] : [20, 40, 220]));
+    expect(paletteOf(halves, 100, 100)).toEqual(['#1428dc:0.50', '#c81e1e:0.50']);
+  });
 });
diff --git a/server/tests/unit/nest/photos/photo-signals.service.test.ts b/server/tests/unit/nest/photos/photo-signals.service.test.ts
index feaae9c8f..54ad63b7f 100644
--- a/server/tests/unit/nest/photos/photo-signals.service.test.ts
+++ b/server/tests/unit/nest/photos/photo-signals.service.test.ts
@@ -311,6 +311,8 @@ describe('PhotoSignalsService, the line', () => {
       algo: PHOTO_SIGNALS_ALGO,
       palette: 'not json',
       busy: 'abc',
+      sal_x: 0.25,
+      sal_y: 0.75,
     });
 
     const book = await main.signals.bookSignals([measured, older, broken, measured]);
@@ -321,7 +323,8 @@ describe('PhotoSignalsService, the line', () => {
     expect(own?.salient).toBeUndefined();
     // An older measurement still knows the size, never the colours.
     expect(book.get(older)).toEqual({ width: 800, height: null, luma: 128 });
-    expect(book.get(broken)).toEqual({ width: null, height: null });
+    // A broken palette or grid reads as none; the salient point beside it still counts.
+    expect(book.get(broken)).toEqual({ width: null, height: null, salient: { x: 0.25, y: 0.75 } });
     expect(await main.signals.bookSignals([])).toEqual(new Map());
   });
 });