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Merged
juliusmarminge merged 7 commits into from
Oct 19, 2026
Merged

fix(desktop): reject offscreen annotation screenshot crops #18441

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e1ad038
fix(desktop): clip design mode captures to visible bounds
maria-rcks Oct 12, 2026
d84aaaf
fix(desktop): reject captures of fully offscreen targets
maria-rcks Oct 12, 2026
3fc838b
chore: merge main
maria-rcks Oct 14, 2026
2173d14
fix(desktop): keep zero-size annotation targets eligible for screenshots
maria-rcks Oct 14, 2026
0b8f095
Merge remote-tracking branch 'origin/main' into fix/design-mode-capture
juliusmarminge Oct 19, 2026
9ee664e
test(desktop): focus annotation capture regression coverage
juliusmarminge Oct 19, 2026
a7fe61d
fix(desktop): clip annotation captures to visible targets
juliusmarminge Oct 19, 2026
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235 changes: 176 additions & 59 deletions apps/desktop/src/preview/Manager.test.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -4179,67 +4179,184 @@ describe("PreviewManager", () => {
),
);

effectIt.effect("crops the picked area out of a full-page capture at device scale", () =>
withManager((manager) =>
Effect.gen(function* () {
let onPicked: ((event: unknown, ...args: unknown[]) => void) | undefined;
const crop = vi.fn((rect: Electron.Rectangle) => ({
getSize: () => ({ width: rect.width, height: rect.height }),
toDataURL: () => "data:image/png;base64,cropped",
}));
const capturePage = vi.fn(async () => ({
getSize: () => ({ width: 2000, height: 1200 }),
crop,
}));
fromId.mockReturnValue(
Object.assign(makeTestPreviewWebContents(capturePage as never), {
isFocused: () => true,
once: vi.fn(),
ipc: {
on: vi.fn((channel: string, listener: typeof onPicked) => {
if (channel === "preview:element-picked") onPicked = listener;
}),
off: vi.fn(),
removeListener: vi.fn(),
},
}),
);
effectIt.effect.each([
["unscaled", { x: 5, y: 6, width: 20, height: 30 }, 1, { x: 5, y: 6, width: 20, height: 30 }],
["retina", { x: 5, y: 6, width: 20, height: 30 }, 2, { x: 10, y: 12, width: 40, height: 60 }],
[
"zoomed retina",
{ x: 5, y: 6, width: 20, height: 30 },
2.5,
{ x: 12, y: 15, width: 51, height: 75 },
],
[
"double zoom retina",
{ x: 5, y: 6, width: 20, height: 30 },
4,
{ x: 20, y: 24, width: 80, height: 120 },
],
[
"clipped top left",
{ x: -5, y: -6, width: 20, height: 30 },
2,
{ x: 0, y: 0, width: 30, height: 48 },
],
[
"clipped bottom right",
{ x: 995, y: 595, width: 20, height: 30 },
2,
{ x: 1990, y: 1190, width: 10, height: 10 },
],
["above viewport", { x: 5, y: -100, width: 20, height: 30 }, 2, null],
["below viewport", { x: 5, y: 601, width: 20, height: 30 }, 2, null],
["left of viewport", { x: -100, y: 6, width: 20, height: 30 }, 2, null],
["right of viewport", { x: 1001, y: 6, width: 20, height: 30 }, 2, null],
[
"padding above viewport",
{ x: 40, y: -100, width: 240, height: 110 },
2,
null,
[{ x: 60, y: -80, width: 200, height: 70 }],
],
[
"padding below viewport",
{ x: 40, y: 590, width: 240, height: 110 },
2,
null,
[{ x: 60, y: 610, width: 200, height: 70 }],
],
[
"padding left of viewport",
{ x: -230, y: 40, width: 240, height: 110 },
2,
null,
[{ x: -210, y: 60, width: 200, height: 70 }],
],
[
"padding right of viewport",
{ x: 990, y: 40, width: 240, height: 110 },
2,
null,
[{ x: 1010, y: 60, width: 200, height: 70 }],
],
[
"opposite offscreen targets",
{ x: -230, y: 40, width: 1460, height: 110 },
2,
null,
[
{ x: -210, y: 60, width: 200, height: 70 },
{ x: 1010, y: 60, width: 200, height: 70 },
],
],
[
"partial target with padding",
{ x: 40, y: -60, width: 240, height: 110 },
2,
{ x: 80, y: 0, width: 480, height: 100 },
[{ x: 60, y: -40, width: 200, height: 70 }],
],
[
"visible and offscreen targets",
{ x: -230, y: 40, width: 510, height: 110 },
2,
{ x: 0, y: 80, width: 560, height: 220 },
[
{ x: -210, y: 60, width: 200, height: 70 },
{ x: 60, y: 60, width: 200, height: 70 },
],
],
[
"offscreen target without crop bounds",
null,
2,
null,
[{ x: 60, y: -80, width: 200, height: 70 }],
],
[
"visible target without crop bounds",
null,
2,
{ x: 0, y: 0, width: 2000, height: 1200 },
[{ x: 60, y: 80, width: 200, height: 70 }],
],
["no targets or crop bounds", null, 2, { x: 0, y: 0, width: 2000, height: 1200 }, []],
] as const)(
"crops the picked viewport area: %s",
([, cropRect, devicePixelRatio, expectedCrop, targetRects]) =>
withManager((manager) =>
Effect.gen(function* () {
let onPicked: ((event: unknown, ...args: unknown[]) => void) | undefined;
const crop = vi.fn((rect: Electron.Rectangle) => ({
getSize: () => ({ width: rect.width, height: rect.height }),
toDataURL: () => "data:image/png;base64,cropped",
}));
const capturePage = vi.fn(async () => ({
getSize: () => ({ width: 2000, height: 1200 }),
toDataURL: () => "data:image/png;base64,cropped",
crop,
}));
fromId.mockReturnValue(
Object.assign(makeTestPreviewWebContents(capturePage as never), {
isFocused: () => true,
once: vi.fn(),
ipc: {
on: vi.fn((channel: string, listener: typeof onPicked) => {
if (channel === "preview:element-picked") onPicked = listener;
}),
off: vi.fn(),
removeListener: vi.fn(),
},
}),
);

yield* manager.createTab("tab_1");
yield* manager.registerWebview("tab_1", 42);
const pick = yield* manager.pickElement("tab_1").pipe(Effect.forkChild);
yield* Effect.yieldNow;
onPicked?.(
{},
{
id: "annotation_1",
pageUrl: "https://example.com",
pageTitle: "Example",
comment: "Tighten this spacing",
elements: [],
regions: [{ id: "region_1", rect: { x: 5, y: 6, width: 20, height: 30 } }],
strokes: [],
styleChanges: [],
screenshot: null,
createdAt: "2026-06-11T00:00:00.000Z",
},
{ x: 5, y: 6, width: 20, height: 30 },
"attach",
2,
);
yield* manager.createTab("tab_1");
yield* manager.registerWebview("tab_1", 42);
const pick = yield* manager.pickElement("tab_1").pipe(Effect.forkChild);
yield* Effect.yieldNow;
onPicked?.(
{},
{
id: "annotation_1",
pageUrl: "https://example.com",
pageTitle: "Example",
comment: "Tighten this spacing",
elements: [],
regions: (targetRects ?? (cropRect ? [cropRect] : [])).map((rect, index) => ({
id: `region_${index}`,
rect,
})),
strokes: [],
styleChanges: [],
screenshot: null,
createdAt: "2026-06-11T00:00:00.000Z",
},
cropRect,
"attach",
devicePixelRatio,
);

const result = yield* Fiber.join(pick);
expect(capturePage).toHaveBeenCalledWith();
expect(crop).toHaveBeenCalledWith({ x: 10, y: 12, width: 40, height: 60 });
expect(result?.screenshotFailed).toBeUndefined();
expect(result?.annotation.screenshot).toEqual({
dataUrl: "data:image/png;base64,cropped",
width: 40,
height: 60,
cropRect: { x: 5, y: 6, width: 20, height: 30 },
});
}),
),
const result = yield* Fiber.join(pick);
expect(capturePage).toHaveBeenCalledWith();
expect(result?.annotation.comment).toBe("Tighten this spacing");
expect(result?.submission).toBe("attach");
expect(webviewSend).toHaveBeenCalledWith("preview:annotation-captured");
if (!expectedCrop) {
expect(crop).not.toHaveBeenCalled();
expect(result?.annotation.screenshot).toBeNull();
expect(result?.screenshotFailed).toBe(true);
return;
}
if (cropRect) expect(crop).toHaveBeenCalledWith(expectedCrop);
else expect(crop).not.toHaveBeenCalled();
expect(result?.screenshotFailed).toBeUndefined();
expect(result?.annotation.screenshot).toEqual({
dataUrl: "data:image/png;base64,cropped",
width: expectedCrop.width,
height: expectedCrop.height,
cropRect: cropRect ?? expectedCrop,
});
}),
),
);

effectIt.effect("a stale capture from a replaced pick never touches the next pick", () =>
Expand Down
48 changes: 39 additions & 9 deletions apps/desktop/src/preview/Manager.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -280,23 +280,42 @@ const normalizeCaptureRect = (value: unknown): PreviewAnnotationRect | null => {
return null;
}
return {
x: Math.max(0, Math.floor(x)),
y: Math.max(0, Math.floor(y)),
x: Math.floor(x),
y: Math.floor(y),
width: Math.max(1, Math.ceil(width)),
height: Math.max(1, Math.ceil(height)),
};
};

/**
* Crops a full-page capture to a picked annotation. `cropRect` is in CSS px;
* Crops a viewport capture to a picked annotation. `cropRect` is in CSS px;
* the capture's pixels are CSS px × the guest's `devicePixelRatio`.
*/
const cropAnnotationScreenshot = (
image: Electron.NativeImage,
cropRect: PreviewAnnotationRect | null,
devicePixelRatio: number,
targetRects: ReadonlyArray<PreviewAnnotationRect>,
): PreviewAnnotationPayload["screenshot"] => {
const full = image.getSize();
if (full.width <= 0 || full.height <= 0) return null;
const scale = Number.isFinite(devicePixelRatio) && devicePixelRatio > 0 ? devicePixelRatio : 1;
// Padding and unions can overlap the viewport without any selected target.
// Check the individual unpadded bounds before accepting even a full capture.
if (
targetRects.length > 0 &&
!targetRects.some(
(rect) =>
rect.width > 0 &&
rect.height > 0 &&
rect.x * scale < full.width &&
rect.y * scale < full.height &&
(rect.x + rect.width) * scale > 0 &&
(rect.y + rect.height) * scale > 0,
)
) {
return null;
}
if (!cropRect) {
return {
dataUrl: image.toDataURL(),
Expand All @@ -305,14 +324,18 @@ const cropAnnotationScreenshot = (
cropRect: { x: 0, y: 0, width: full.width, height: full.height },
};
}
const scale = Number.isFinite(devicePixelRatio) && devicePixelRatio > 0 ? devicePixelRatio : 1;
const x = Math.min(full.width - 1, Math.max(0, Math.floor(cropRect.x * scale)));
const y = Math.min(full.height - 1, Math.max(0, Math.floor(cropRect.y * scale)));
const x = Math.max(0, Math.floor(cropRect.x * scale));
const y = Math.max(0, Math.floor(cropRect.y * scale));
const right = Math.min(full.width, Math.ceil((cropRect.x + cropRect.width) * scale));
const bottom = Math.min(full.height, Math.ceil((cropRect.y + cropRect.height) * scale));
// A target scrolled out of view has no pixels in this capture. Clamping its
// origin onto the edge would attach an unrelated strip as a successful crop.
if (right <= x || bottom <= y) return null;
const cropped = image.crop({
x,
y,
width: Math.max(1, Math.min(full.width - x, Math.ceil(cropRect.width * scale))),
height: Math.max(1, Math.min(full.height - y, Math.ceil(cropRect.height * scale))),
width: right - x,
height: bottom - y,
});
const size = cropped.getSize();
return { dataUrl: cropped.toDataURL(), width: size.width, height: size.height, cropRect };
Expand Down Expand Up @@ -2255,6 +2278,11 @@ const makeNativeOperations = Effect.fn("PreviewManager.makeOperations")(function
const submission =
args[2] === "send" && annotationSendEnabled.get(tabId) === true ? "send" : "attach";
const devicePixelRatio = typeof args[3] === "number" ? args[3] : 1;
const targetRects = [
...payload.elements.map((target) => target.rect),
...payload.regions.map((target) => target.rect),
...payload.strokes.map((target) => target.bounds),
];
runFork(
// The full-page capture with retries is what the screenshot button
// uses. A single cropped `capturePage(rect)` with a fixed timeout
Expand All @@ -2264,7 +2292,9 @@ const makeNativeOperations = Effect.fn("PreviewManager.makeOperations")(function
tabId,
wc,
).pipe(
Effect.map((image) => cropAnnotationScreenshot(image, cropRect, devicePixelRatio)),
Effect.map((image) =>
cropAnnotationScreenshot(image, cropRect, devicePixelRatio, targetRects),
),
Effect.tapError((error) =>
Effect.logWarning("preview annotation screenshot failed").pipe(
Effect.annotateLogs({ tabId, webContentsId: wc.id, error: error.message }),
Expand Down
16 changes: 7 additions & 9 deletions apps/desktop/src/preview/PickPreload.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -257,15 +257,13 @@ function unionRects(
const top = Math.min(...rects.map((rect) => rect.y));
const right = Math.max(...rects.map((rect) => rect.x + rect.width));
const bottom = Math.max(...rects.map((rect) => rect.y + rect.height));
const x = Math.max(0, left - padding);
const y = Math.max(0, top - padding);
const maxWidth = Math.max(1, window.innerWidth - x);
const maxHeight = Math.max(1, window.innerHeight - y);
// Keep offscreen bounds intact; main intersects them with the captured
// viewport instead of moving an invisible selection onto unrelated pixels.
return {
x,
y,
width: Math.min(maxWidth, right - left + padding * 2),
height: Math.min(maxHeight, bottom - top + padding * 2),
x: left - padding,
y: top - padding,
width: right - left + padding * 2,
height: bottom - top + padding * 2,
};
}

Expand Down Expand Up @@ -1452,7 +1450,7 @@ function startAnnotation(sendEnabled: boolean): void {
annotation,
screenshotRect,
submission === "send" && !sendEnabled ? "attach" : submission,
// Main crops a full-page capture, whose pixels are CSS px × this.
// Main crops a viewport capture, whose pixels are CSS px × this.
window.devicePixelRatio,
);
})
Expand Down
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