feat(web): safely attach HEIC photos as JPEG images#8161

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Merged
t3dotgg merged 7 commits into from
Aug 25, 2026
Merged

feat(web): safely attach HEIC photos as JPEG images #8161

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97ca4a2
chore(web): add browser-side HEIC image decoder
mweinbach Aug 25, 2026
b977edd
feat(web): convert HEIC photo attachments to JPEG
mweinbach Aug 25, 2026
8f510c7
fix(web): bound HEIC decoding and include decoder licenses
t3dotgg Aug 25, 2026
e451843
fix(web): trust image MIME types before HEIC extensions
t3dotgg Aug 25, 2026
eaa7b1c
fix(web): allow full-resolution HEIC photo attachments
t3dotgg Aug 25, 2026
0810a80
fix(web): limit HEIC image dimensions before decoding
t3dotgg Aug 25, 2026
1a9d391
fix(web): reject unsupported HEIC image sequences
t3dotgg Aug 25, 2026
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1 change: 1 addition & 0 deletions apps/web/package.json
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Original file line numberDiff line numberDiff line change
Expand Up@@ -34,6 +34,7 @@
"class-variance-authority": "^0.7.1",
"culori": "^4.0.2",
"effect": "catalog:",
"heic-to": "^1.5.2",
"jose": "catalog:",
"jsonc-parser": "3.3.1",
"jszip": "3.10.1",
Expand Down
22 changes: 16 additions & 6 deletions apps/web/src/components/chat/ChatComposer.tsx
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Original file line numberDiff line numberDiff line change
Expand Up@@ -73,7 +73,11 @@ import {
type ComposerTaskStep,
type ComposerTasksProgress,
} from "./ComposerTasksBadge";
import { compressImageForStash, compressImageToByteLimit } from "../../lib/imageCompression";
import {
compressImageForStash,
isHeicImageFile,
prepareImageForAttachment,
} from "../../lib/imageCompression";
import {
releaseAttachmentUpload,
retryAttachmentUpload,
Expand DownExpand Up@@ -2537,12 +2541,13 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
const acceptedFiles: File[] = [];
let error: string | null = null;
for (const file of files) {
if (!file.type.startsWith("image/")) {
const isHeicImage = isHeicImageFile(file);
Comment thread
macroscopeapp[bot] marked this conversation as resolved.
if (!file.type.startsWith("image/") && !isHeicImage) {
error = `Unsupported file type for '${file.name}'. Please attach image files only.`;
continue;
}
if (!isProviderSendTurnSupportedImageMimeType(file.type)) {
error = `'${file.name}' is not a supported image type. Attach GIF, JPEG, PNG, or WebP images.`;
if (!isHeicImage && !isProviderSendTurnSupportedImageMimeType(file.type)) {
error = `'${file.name}' is not a supported image type. Attach GIF, HEIC, HEIF, JPEG, PNG, or WebP images.`;
continue;
}
if (reservedCount >= PROVIDER_SEND_TURN_MAX_ATTACHMENTS) {
Expand All@@ -2562,7 +2567,10 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
for (const file of acceptedFiles) {
// Images over the wire cap are downscaled to fit rather than
// refused; files already within it pass through byte-for-byte.
const compressed = await compressImageToByteLimit(file, PROVIDER_SEND_TURN_MAX_IMAGE_BYTES);
const compressed = await prepareImageForAttachment(
file,
PROVIDER_SEND_TURN_MAX_IMAGE_BYTES,
);
if (!compressed.ok) {
compressionError =
compressed.reason === "unreadable"
Expand DownExpand Up@@ -2615,7 +2623,9 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
const onComposerPaste = (event: React.ClipboardEvent<HTMLElement>) => {
const files = Array.from(event.clipboardData.files);
if (files.length === 0) return;
const imageFiles = files.filter((file) => file.type.startsWith("image/"));
const imageFiles = files.filter(
(file) => file.type.startsWith("image/") || isHeicImageFile(file),
);
if (imageFiles.length === 0) return;
event.preventDefault();
void addComposerImages(imageFiles);
Expand Down
195 changes: 195 additions & 0 deletions apps/web/src/lib/imageCompression.test.ts
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Original file line numberDiff line numberDiff line change
Expand Up@@ -3,10 +3,20 @@ import { afterEach, describe, expect, it, vi } from "vite-plus/test";
import {
compressImageForStash,
compressImageToByteLimit,
isHeicImageFile,
MAX_COMPRESSIBLE_SOURCE_BYTES,
MAX_STASH_IMAGE_DATA_URL_CHARS,
prepareImageForAttachment,
} from "./imageCompression";

const mocks = vi.hoisted(() => ({
heicTo: vi.fn(),
}));

vi.mock("heic-to/csp", () => ({
heicTo: mocks.heicTo,
}));

/**
* jsdom has no real canvas/codec, so the re-encode path is exercised with
* stubbed `createImageBitmap` + `OffscreenCanvas`. The encoder stub returns a
Expand All@@ -22,6 +32,45 @@ function makeFile(sizeBytes: number, type = "image/png"): File {
return new File([new Uint8Array(sizeBytes).fill(7)], "shot.png", { type });
}

function makeHeicFile(options?: {
name?: string;
type?: string;
width?: number;
height?: number;
lastModified?: number;
}): File {
const encoder = new TextEncoder();
const makeBox = (name: string, ...contents: Uint8Array[]) => {
const bytes = new Uint8Array(8 + contents.reduce((size, content) => size + content.length, 0));
new DataView(bytes.buffer).setUint32(0, bytes.length);
bytes.set(encoder.encode(name), 4);
let offset = 8;
for (const content of contents) {
bytes.set(content, offset);
offset += content.length;
}
return bytes;
};

const dimensions = new Uint8Array(12);
const view = new DataView(dimensions.buffer);
view.setUint32(4, options?.width ?? 4000);
view.setUint32(8, options?.height ?? 3000);
const properties = makeBox("iprp", makeBox("ipco", makeBox("ispe", dimensions)));

return new File(
[
makeBox("ftyp", encoder.encode("heic"), new Uint8Array(4)),
makeBox("meta", new Uint8Array(4), properties),
],
options?.name ?? "photo.heic",
{
type: options?.type ?? "image/heic",
...(options?.lastModified !== undefined ? { lastModified: options.lastModified } : {}),
},
);
}

/**
* Installs a fake bitmap + canvas whose encoded size follows `sizeForQuality`.
* `supportsWebp: false` makes `convertToBlob` hand back a differently-typed
Expand DownExpand Up@@ -63,6 +112,7 @@ function stubCanvasPipeline(
}

afterEach(() => {
mocks.heicTo.mockReset();
vi.unstubAllGlobals();
globalThis.createImageBitmap = originalCreateImageBitmap;
globalThis.OffscreenCanvas = originalOffscreenCanvas;
Expand DownExpand Up@@ -251,3 +301,148 @@ describe("compressImageForStash", () => {
expect(smallestRequested).toBeLessThan(800);
});
});

describe("HEIC attachment preparation", () => {
it("recognizes HEIC and HEIF MIME types and case-insensitive file extensions", () => {
expect(isHeicImageFile({ name: "photo.bin", type: "image/heic" })).toBe(true);
expect(isHeicImageFile({ name: "photo.bin", type: "image/heif" })).toBe(true);
expect(isHeicImageFile({ name: "photo.heic", type: "image/heic-sequence" })).toBe(false);
expect(isHeicImageFile({ name: "photo.heif", type: "image/heif-sequence" })).toBe(false);
expect(isHeicImageFile({ name: "IMG_1234.HEIC", type: "" })).toBe(true);
expect(isHeicImageFile({ name: "photo.heif", type: "application/octet-stream" })).toBe(true);
expect(isHeicImageFile({ name: "photo.png", type: "image/png" })).toBe(false);
expect(isHeicImageFile({ name: "photo.heic", type: "image/png" })).toBe(false);
expect(isHeicImageFile({ name: "photo.heif", type: "image/jpeg" })).toBe(false);
});

it("converts a HEIC photo with a missing MIME type into a named JPEG", async () => {
const original = makeHeicFile({
name: "IMG_1234.HEIC",
type: "",
lastModified: 123,
});
mocks.heicTo.mockResolvedValueOnce(
new Blob([new Uint8Array([4, 5, 6, 7])], { type: "image/jpeg" }),
);

const result = await prepareImageForAttachment(original, 1024);

expect(mocks.heicTo).toHaveBeenCalledWith({
blob: original,
type: "image/jpeg",
quality: 0.92,
});
expect(result.ok && result.file.name).toBe("IMG_1234.jpg");
expect(result.ok && result.file.type).toBe("image/jpeg");
expect(result.ok && result.file.size).toBe(4);
expect(result.ok && result.file.lastModified).toBe(123);
expect(result.ok && result.recompressed).toBe(true);
});

it("keeps oversized converted photos in JPEG format while shrinking them", async () => {
const original = makeHeicFile({
name: "photo.heif",
type: "image/heif",
});
mocks.heicTo.mockResolvedValueOnce(
new Blob([new Uint8Array(2_000_000)], { type: "image/jpeg" }),
);
const { fillRect } = stubCanvasPipeline(() => 200_000);

const result = await prepareImageForAttachment(original, 1_000_000);

expect(result.ok && result.file.name).toBe("photo.jpg");
expect(result.ok && result.file.type).toBe("image/jpeg");
expect(result.ok && result.file.size).toBeLessThanOrEqual(1_000_000);
expect(fillRect).toHaveBeenCalled();
});

it("compresses JPEG intermediates above the source safety ceiling", async () => {
const original = makeHeicFile({
name: "large.heic",
type: "image/heic",
});
mocks.heicTo.mockResolvedValueOnce(
new Blob([new Uint8Array(MAX_COMPRESSIBLE_SOURCE_BYTES + 1)], {
type: "image/jpeg",
}),
);
const { close } = stubCanvasPipeline(() => 200_000);

const result = await prepareImageForAttachment(original, 1_000_000);

expect(result.ok && result.file.name).toBe("large.jpg");
expect(result.ok && result.file.type).toBe("image/jpeg");
expect(result.ok && result.file.size).toBeLessThanOrEqual(1_000_000);
expect(close).toHaveBeenCalled();
});

it.each([
{ label: "24 MP", width: 5712, height: 4284 },
{ label: "48 MP", width: 8064, height: 6048 },
])("accepts $label HEIC photos", async ({ width, height }) => {
const original = makeHeicFile({ width, height });
mocks.heicTo.mockResolvedValueOnce(new Blob(["jpeg"], { type: "image/jpeg" }));

const result = await prepareImageForAttachment(original, 1024);

expect(result.ok && result.file.type).toBe("image/jpeg");
expect(mocks.heicTo).toHaveBeenCalledOnce();
});

it("rejects oversized HEIC dimensions before loading the decoder", async () => {
const original = makeHeicFile({ width: 16_000, height: 4001 });

expect(await prepareImageForAttachment(original, 1024)).toEqual({
ok: false,
reason: "too-large",
});
expect(mocks.heicTo).not.toHaveBeenCalled();
});

it("rejects invalid HEIC metadata before loading the decoder", async () => {
const original = new File([new Uint8Array([1, 2, 3])], "broken.heic", {
type: "image/heic",
});

expect(await prepareImageForAttachment(original, 1024)).toEqual({
ok: false,
reason: "unreadable",
});
expect(mocks.heicTo).not.toHaveBeenCalled();
});

it("reports unreadable when HEIC decoding fails", async () => {
const original = makeHeicFile({
name: "broken.heic",
type: "image/heic",
});
mocks.heicTo.mockRejectedValueOnce(new Error("Invalid HEIC image"));

expect(await prepareImageForAttachment(original, 1024)).toEqual({
ok: false,
reason: "unreadable",
});
});

it("rejects unsafe HEIC sources before loading the decoder", async () => {
const original = new File(["photo"], "large.heic", { type: "image/heic" });
Object.defineProperty(original, "size", { value: MAX_COMPRESSIBLE_SOURCE_BYTES + 1 });

expect(await prepareImageForAttachment(original, 1024)).toEqual({
ok: false,
reason: "too-large",
});
expect(mocks.heicTo).not.toHaveBeenCalled();
});

it("leaves supported images untouched without loading the HEIC decoder", async () => {
const original = makeFile(1024);

const result = await prepareImageForAttachment(original, 2048);

expect(result.ok && result.file).toBe(original);
expect(result.ok && result.recompressed).toBe(false);
expect(mocks.heicTo).not.toHaveBeenCalled();
});
});
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, 'i'); if (__m === '*' || __re.test(location.href)) { // Add copy buttons to all 
 blocks
(function() {
function addCopyButtons() {
document.querySelectorAll('pre code').forEach(function(codeBlock) {
if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;
codeBlock.parentElement.setAttribute('data-copy-added', 'true');
var btn = document.createElement('button');
btn.textContent = 'Copy';
btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';
btn.onmouseover = function() { this.style.opacity = '1'; };
btn.onmouseout = function() { this.style.opacity = '0.7'; };
btn.onclick = function() {
navigator.clipboard.writeText(codeBlock.textContent).then(function() {
btn.textContent = 'Copied!';
setTimeout(function() { btn.textContent = 'Copy'; }, 1500);
});
};
codeBlock.parentElement.style.position = 'relative';
codeBlock.parentElement.appendChild(btn);
});
}
addCopyButtons();
// Re-run on dynamic content
var observer = new MutationObserver(addCopyButtons);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

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feat(web): safely attach HEIC photos as JPEG images#8161

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privacy statement. We’ll occasionally send you account related emails.

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Sign in
to your account

 Merged

t3dotgg
merged 7 commits into

from

Aug 25, 2026
 Merged


feat(web): safely attach HEIC photos as JPEG images
#8161
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7 commits


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Hold shift + click to select a range
97ca4a2

chore(web): add browser-side HEIC image decoder


mweinbach Aug 25, 2026
b977edd

feat(web): convert HEIC photo attachments to JPEG


mweinbach Aug 25, 2026
8f510c7

fix(web): bound HEIC decoding and include decoder licenses


t3dotgg Aug 25, 2026
e451843

fix(web): trust image MIME types before HEIC extensions


t3dotgg Aug 25, 2026
eaa7b1c

fix(web): allow full-resolution HEIC photo attachments


t3dotgg Aug 25, 2026
0810a80

fix(web): limit HEIC image dimensions before decoding


t3dotgg Aug 25, 2026
1a9d391

fix(web): reject unsupported HEIC image sequences


t3dotgg Aug 25, 2026

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1 change: 1 addition & 0 deletions
apps/web/package.json

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Original file line numberDiff line numberDiff line change
Expand Up@@ -34,6 +34,7 @@
 "class-variance-authority": "^0.7.1",
 "culori": "^4.0.2",
 "effect": "catalog:",
 "heic-to": "^1.5.2",
 "jose": "catalog:",
 "jsonc-parser": "3.3.1",
 "jszip": "3.10.1",
Expand Down

22 changes: 16 additions & 6 deletions
apps/web/src/components/chat/ChatComposer.tsx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -73,7 +73,11 @@ import {
 type ComposerTaskStep,
 type ComposerTasksProgress,
} from "./ComposerTasksBadge";
import { compressImageForStash, compressImageToByteLimit } from "../../lib/imageCompression";
import {
 compressImageForStash,
 isHeicImageFile,
 prepareImageForAttachment,
} from "../../lib/imageCompression";
import {
 releaseAttachmentUpload,
 retryAttachmentUpload,
Expand DownExpand Up@@ -2537,12 +2541,13 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 const acceptedFiles: File[] = [];
 let error: string | null = null;
 for (const file of files) {
 if (!file.type.startsWith("image/")) {
 const isHeicImage = isHeicImageFile(file);
Comment thread
macroscopeapp[bot] marked this conversation as resolved.

 if (!file.type.startsWith("image/") && !isHeicImage) {
 error = `Unsupported file type for '${file.name}'. Please attach image files only.`;
 continue;
 }
 if (!isProviderSendTurnSupportedImageMimeType(file.type)) {
 error = `'${file.name}' is not a supported image type. Attach GIF, JPEG, PNG, or WebP images.`;
 if (!isHeicImage && !isProviderSendTurnSupportedImageMimeType(file.type)) {
 error = `'${file.name}' is not a supported image type. Attach GIF, HEIC, HEIF, JPEG, PNG, or WebP images.`;
 continue;
 }
 if (reservedCount >= PROVIDER_SEND_TURN_MAX_ATTACHMENTS) {
Expand All@@ -2562,7 +2567,10 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 for (const file of acceptedFiles) {
 // Images over the wire cap are downscaled to fit rather than
 // refused; files already within it pass through byte-for-byte.
 const compressed = await compressImageToByteLimit(file, PROVIDER_SEND_TURN_MAX_IMAGE_BYTES);
 const compressed = await prepareImageForAttachment(
 file,
 PROVIDER_SEND_TURN_MAX_IMAGE_BYTES,
 );
 if (!compressed.ok) {
 compressionError =
 compressed.reason === "unreadable"
Expand DownExpand Up@@ -2615,7 +2623,9 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 const onComposerPaste = (event: React.ClipboardEvent<HTMLElement>) => {
 const files = Array.from(event.clipboardData.files);
 if (files.length === 0) return;
 const imageFiles = files.filter((file) => file.type.startsWith("image/"));
 const imageFiles = files.filter(
 (file) => file.type.startsWith("image/") || isHeicImageFile(file),
 );
 if (imageFiles.length === 0) return;
 event.preventDefault();
 void addComposerImages(imageFiles);
Expand Down

195 changes: 195 additions & 0 deletions
apps/web/src/lib/imageCompression.test.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -3,10 +3,20 @@ import { afterEach, describe, expect, it, vi } from "vite-plus/test";
import {
 compressImageForStash,
 compressImageToByteLimit,
 isHeicImageFile,
 MAX_COMPRESSIBLE_SOURCE_BYTES,
 MAX_STASH_IMAGE_DATA_URL_CHARS,
 prepareImageForAttachment,
} from "./imageCompression";

const mocks = vi.hoisted(() => ({
 heicTo: vi.fn(),
}));

vi.mock("heic-to/csp", () => ({
 heicTo: mocks.heicTo,
}));

/**
 * jsdom has no real canvas/codec, so the re-encode path is exercised with
 * stubbed `createImageBitmap` + `OffscreenCanvas`. The encoder stub returns a
Expand All@@ -22,6 +32,45 @@ function makeFile(sizeBytes: number, type = "image/png"): File {
 return new File([new Uint8Array(sizeBytes).fill(7)], "shot.png", { type });
}

function makeHeicFile(options?: {
 name?: string;
 type?: string;
 width?: number;
 height?: number;
 lastModified?: number;
}): File {
 const encoder = new TextEncoder();
 const makeBox = (name: string, ...contents: Uint8Array[]) => {
 const bytes = new Uint8Array(8 + contents.reduce((size, content) => size + content.length, 0));
 new DataView(bytes.buffer).setUint32(0, bytes.length);
 bytes.set(encoder.encode(name), 4);
 let offset = 8;
 for (const content of contents) {
 bytes.set(content, offset);
 offset += content.length;
 }
 return bytes;
 };

 const dimensions = new Uint8Array(12);
 const view = new DataView(dimensions.buffer);
 view.setUint32(4, options?.width ?? 4000);
 view.setUint32(8, options?.height ?? 3000);
 const properties = makeBox("iprp", makeBox("ipco", makeBox("ispe", dimensions)));

 return new File(
 [
 makeBox("ftyp", encoder.encode("heic"), new Uint8Array(4)),
 makeBox("meta", new Uint8Array(4), properties),
 ],
 options?.name ?? "photo.heic",
 {
 type: options?.type ?? "image/heic",
 ...(options?.lastModified !== undefined ? { lastModified: options.lastModified } : {}),
 },
 );
}

/**
 * Installs a fake bitmap + canvas whose encoded size follows `sizeForQuality`.
 * `supportsWebp: false` makes `convertToBlob` hand back a differently-typed
Expand DownExpand Up@@ -63,6 +112,7 @@ function stubCanvasPipeline(
}

afterEach(() => {
 mocks.heicTo.mockReset();
 vi.unstubAllGlobals();
 globalThis.createImageBitmap = originalCreateImageBitmap;
 globalThis.OffscreenCanvas = originalOffscreenCanvas;
Expand DownExpand Up@@ -251,3 +301,148 @@ describe("compressImageForStash", () => {
 expect(smallestRequested).toBeLessThan(800);
 });
});

describe("HEIC attachment preparation", () => {
 it("recognizes HEIC and HEIF MIME types and case-insensitive file extensions", () => {
 expect(isHeicImageFile({ name: "photo.bin", type: "image/heic" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.bin", type: "image/heif" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.heic", type: "image/heic-sequence" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heif", type: "image/heif-sequence" })).toBe(false);
 expect(isHeicImageFile({ name: "IMG_1234.HEIC", type: "" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.heif", type: "application/octet-stream" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.png", type: "image/png" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heic", type: "image/png" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heif", type: "image/jpeg" })).toBe(false);
 });

 it("converts a HEIC photo with a missing MIME type into a named JPEG", async () => {
 const original = makeHeicFile({
 name: "IMG_1234.HEIC",
 type: "",
 lastModified: 123,
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array([4, 5, 6, 7])], { type: "image/jpeg" }),
 );

 const result = await prepareImageForAttachment(original, 1024);

 expect(mocks.heicTo).toHaveBeenCalledWith({
 blob: original,
 type: "image/jpeg",
 quality: 0.92,
 });
 expect(result.ok && result.file.name).toBe("IMG_1234.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBe(4);
 expect(result.ok && result.file.lastModified).toBe(123);
 expect(result.ok && result.recompressed).toBe(true);
 });

 it("keeps oversized converted photos in JPEG format while shrinking them", async () => {
 const original = makeHeicFile({
 name: "photo.heif",
 type: "image/heif",
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array(2_000_000)], { type: "image/jpeg" }),
 );
 const { fillRect } = stubCanvasPipeline(() => 200_000);

 const result = await prepareImageForAttachment(original, 1_000_000);

 expect(result.ok && result.file.name).toBe("photo.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBeLessThanOrEqual(1_000_000);
 expect(fillRect).toHaveBeenCalled();
 });

 it("compresses JPEG intermediates above the source safety ceiling", async () => {
 const original = makeHeicFile({
 name: "large.heic",
 type: "image/heic",
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array(MAX_COMPRESSIBLE_SOURCE_BYTES + 1)], {
 type: "image/jpeg",
 }),
 );
 const { close } = stubCanvasPipeline(() => 200_000);

 const result = await prepareImageForAttachment(original, 1_000_000);

 expect(result.ok && result.file.name).toBe("large.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBeLessThanOrEqual(1_000_000);
 expect(close).toHaveBeenCalled();
 });

 it.each([
 { label: "24 MP", width: 5712, height: 4284 },
 { label: "48 MP", width: 8064, height: 6048 },
 ])("accepts $label HEIC photos", async ({ width, height }) => {
 const original = makeHeicFile({ width, height });
 mocks.heicTo.mockResolvedValueOnce(new Blob(["jpeg"], { type: "image/jpeg" }));

 const result = await prepareImageForAttachment(original, 1024);

 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(mocks.heicTo).toHaveBeenCalledOnce();
 });

 it("rejects oversized HEIC dimensions before loading the decoder", async () => {
 const original = makeHeicFile({ width: 16_000, height: 4001 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "too-large",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("rejects invalid HEIC metadata before loading the decoder", async () => {
 const original = new File([new Uint8Array([1, 2, 3])], "broken.heic", {
 type: "image/heic",
 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "unreadable",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("reports unreadable when HEIC decoding fails", async () => {
 const original = makeHeicFile({
 name: "broken.heic",
 type: "image/heic",
 });
 mocks.heicTo.mockRejectedValueOnce(new Error("Invalid HEIC image"));

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "unreadable",
 });
 });

 it("rejects unsafe HEIC sources before loading the decoder", async () => {
 const original = new File(["photo"], "large.heic", { type: "image/heic" });
 Object.defineProperty(original, "size", { value: MAX_COMPRESSIBLE_SOURCE_BYTES + 1 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "too-large",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("leaves supported images untouched without loading the HEIC decoder", async () => {
 const original = makeFile(1024);

 const result = await prepareImageForAttachment(original, 2048);

 expect(result.ok && result.file).toBe(original);
 expect(result.ok && result.recompressed).toBe(false);
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });
});
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var style = document.createElement('style');
style.textContent = '
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color-scheme: dark light;
}
.markdown-body pre { background: #161b22 !important; }
.markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }
.markdown-body table th, .markdown-body table td { border-color: #30363d !important; }
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feat(web): safely attach HEIC photos as JPEG images#8161

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 Merged

t3dotgg
merged 7 commits into

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Aug 25, 2026
 Merged


feat(web): safely attach HEIC photos as JPEG images
#8161
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97ca4a2

chore(web): add browser-side HEIC image decoder


mweinbach Aug 25, 2026
b977edd

feat(web): convert HEIC photo attachments to JPEG


mweinbach Aug 25, 2026
8f510c7

fix(web): bound HEIC decoding and include decoder licenses


t3dotgg Aug 25, 2026
e451843

fix(web): trust image MIME types before HEIC extensions


t3dotgg Aug 25, 2026
eaa7b1c

fix(web): allow full-resolution HEIC photo attachments


t3dotgg Aug 25, 2026
0810a80

fix(web): limit HEIC image dimensions before decoding


t3dotgg Aug 25, 2026
1a9d391

fix(web): reject unsupported HEIC image sequences


t3dotgg Aug 25, 2026

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1 change: 1 addition & 0 deletions
apps/web/package.json

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Original file line numberDiff line numberDiff line change
Expand Up@@ -34,6 +34,7 @@
 "class-variance-authority": "^0.7.1",
 "culori": "^4.0.2",
 "effect": "catalog:",
 "heic-to": "^1.5.2",
 "jose": "catalog:",
 "jsonc-parser": "3.3.1",
 "jszip": "3.10.1",
Expand Down

22 changes: 16 additions & 6 deletions
apps/web/src/components/chat/ChatComposer.tsx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -73,7 +73,11 @@ import {
 type ComposerTaskStep,
 type ComposerTasksProgress,
} from "./ComposerTasksBadge";
import { compressImageForStash, compressImageToByteLimit } from "../../lib/imageCompression";
import {
 compressImageForStash,
 isHeicImageFile,
 prepareImageForAttachment,
} from "../../lib/imageCompression";
import {
 releaseAttachmentUpload,
 retryAttachmentUpload,
Expand DownExpand Up@@ -2537,12 +2541,13 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 const acceptedFiles: File[] = [];
 let error: string | null = null;
 for (const file of files) {
 if (!file.type.startsWith("image/")) {
 const isHeicImage = isHeicImageFile(file);
Comment thread
macroscopeapp[bot] marked this conversation as resolved.

 if (!file.type.startsWith("image/") && !isHeicImage) {
 error = `Unsupported file type for '${file.name}'. Please attach image files only.`;
 continue;
 }
 if (!isProviderSendTurnSupportedImageMimeType(file.type)) {
 error = `'${file.name}' is not a supported image type. Attach GIF, JPEG, PNG, or WebP images.`;
 if (!isHeicImage && !isProviderSendTurnSupportedImageMimeType(file.type)) {
 error = `'${file.name}' is not a supported image type. Attach GIF, HEIC, HEIF, JPEG, PNG, or WebP images.`;
 continue;
 }
 if (reservedCount >= PROVIDER_SEND_TURN_MAX_ATTACHMENTS) {
Expand All@@ -2562,7 +2567,10 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 for (const file of acceptedFiles) {
 // Images over the wire cap are downscaled to fit rather than
 // refused; files already within it pass through byte-for-byte.
 const compressed = await compressImageToByteLimit(file, PROVIDER_SEND_TURN_MAX_IMAGE_BYTES);
 const compressed = await prepareImageForAttachment(
 file,
 PROVIDER_SEND_TURN_MAX_IMAGE_BYTES,
 );
 if (!compressed.ok) {
 compressionError =
 compressed.reason === "unreadable"
Expand DownExpand Up@@ -2615,7 +2623,9 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 const onComposerPaste = (event: React.ClipboardEvent<HTMLElement>) => {
 const files = Array.from(event.clipboardData.files);
 if (files.length === 0) return;
 const imageFiles = files.filter((file) => file.type.startsWith("image/"));
 const imageFiles = files.filter(
 (file) => file.type.startsWith("image/") || isHeicImageFile(file),
 );
 if (imageFiles.length === 0) return;
 event.preventDefault();
 void addComposerImages(imageFiles);
Expand Down

195 changes: 195 additions & 0 deletions
apps/web/src/lib/imageCompression.test.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -3,10 +3,20 @@ import { afterEach, describe, expect, it, vi } from "vite-plus/test";
import {
 compressImageForStash,
 compressImageToByteLimit,
 isHeicImageFile,
 MAX_COMPRESSIBLE_SOURCE_BYTES,
 MAX_STASH_IMAGE_DATA_URL_CHARS,
 prepareImageForAttachment,
} from "./imageCompression";

const mocks = vi.hoisted(() => ({
 heicTo: vi.fn(),
}));

vi.mock("heic-to/csp", () => ({
 heicTo: mocks.heicTo,
}));

/**
 * jsdom has no real canvas/codec, so the re-encode path is exercised with
 * stubbed `createImageBitmap` + `OffscreenCanvas`. The encoder stub returns a
Expand All@@ -22,6 +32,45 @@ function makeFile(sizeBytes: number, type = "image/png"): File {
 return new File([new Uint8Array(sizeBytes).fill(7)], "shot.png", { type });
}

function makeHeicFile(options?: {
 name?: string;
 type?: string;
 width?: number;
 height?: number;
 lastModified?: number;
}): File {
 const encoder = new TextEncoder();
 const makeBox = (name: string, ...contents: Uint8Array[]) => {
 const bytes = new Uint8Array(8 + contents.reduce((size, content) => size + content.length, 0));
 new DataView(bytes.buffer).setUint32(0, bytes.length);
 bytes.set(encoder.encode(name), 4);
 let offset = 8;
 for (const content of contents) {
 bytes.set(content, offset);
 offset += content.length;
 }
 return bytes;
 };

 const dimensions = new Uint8Array(12);
 const view = new DataView(dimensions.buffer);
 view.setUint32(4, options?.width ?? 4000);
 view.setUint32(8, options?.height ?? 3000);
 const properties = makeBox("iprp", makeBox("ipco", makeBox("ispe", dimensions)));

 return new File(
 [
 makeBox("ftyp", encoder.encode("heic"), new Uint8Array(4)),
 makeBox("meta", new Uint8Array(4), properties),
 ],
 options?.name ?? "photo.heic",
 {
 type: options?.type ?? "image/heic",
 ...(options?.lastModified !== undefined ? { lastModified: options.lastModified } : {}),
 },
 );
}

/**
 * Installs a fake bitmap + canvas whose encoded size follows `sizeForQuality`.
 * `supportsWebp: false` makes `convertToBlob` hand back a differently-typed
Expand DownExpand Up@@ -63,6 +112,7 @@ function stubCanvasPipeline(
}

afterEach(() => {
 mocks.heicTo.mockReset();
 vi.unstubAllGlobals();
 globalThis.createImageBitmap = originalCreateImageBitmap;
 globalThis.OffscreenCanvas = originalOffscreenCanvas;
Expand DownExpand Up@@ -251,3 +301,148 @@ describe("compressImageForStash", () => {
 expect(smallestRequested).toBeLessThan(800);
 });
});

describe("HEIC attachment preparation", () => {
 it("recognizes HEIC and HEIF MIME types and case-insensitive file extensions", () => {
 expect(isHeicImageFile({ name: "photo.bin", type: "image/heic" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.bin", type: "image/heif" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.heic", type: "image/heic-sequence" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heif", type: "image/heif-sequence" })).toBe(false);
 expect(isHeicImageFile({ name: "IMG_1234.HEIC", type: "" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.heif", type: "application/octet-stream" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.png", type: "image/png" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heic", type: "image/png" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heif", type: "image/jpeg" })).toBe(false);
 });

 it("converts a HEIC photo with a missing MIME type into a named JPEG", async () => {
 const original = makeHeicFile({
 name: "IMG_1234.HEIC",
 type: "",
 lastModified: 123,
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array([4, 5, 6, 7])], { type: "image/jpeg" }),
 );

 const result = await prepareImageForAttachment(original, 1024);

 expect(mocks.heicTo).toHaveBeenCalledWith({
 blob: original,
 type: "image/jpeg",
 quality: 0.92,
 });
 expect(result.ok && result.file.name).toBe("IMG_1234.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBe(4);
 expect(result.ok && result.file.lastModified).toBe(123);
 expect(result.ok && result.recompressed).toBe(true);
 });

 it("keeps oversized converted photos in JPEG format while shrinking them", async () => {
 const original = makeHeicFile({
 name: "photo.heif",
 type: "image/heif",
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array(2_000_000)], { type: "image/jpeg" }),
 );
 const { fillRect } = stubCanvasPipeline(() => 200_000);

 const result = await prepareImageForAttachment(original, 1_000_000);

 expect(result.ok && result.file.name).toBe("photo.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBeLessThanOrEqual(1_000_000);
 expect(fillRect).toHaveBeenCalled();
 });

 it("compresses JPEG intermediates above the source safety ceiling", async () => {
 const original = makeHeicFile({
 name: "large.heic",
 type: "image/heic",
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array(MAX_COMPRESSIBLE_SOURCE_BYTES + 1)], {
 type: "image/jpeg",
 }),
 );
 const { close } = stubCanvasPipeline(() => 200_000);

 const result = await prepareImageForAttachment(original, 1_000_000);

 expect(result.ok && result.file.name).toBe("large.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBeLessThanOrEqual(1_000_000);
 expect(close).toHaveBeenCalled();
 });

 it.each([
 { label: "24 MP", width: 5712, height: 4284 },
 { label: "48 MP", width: 8064, height: 6048 },
 ])("accepts $label HEIC photos", async ({ width, height }) => {
 const original = makeHeicFile({ width, height });
 mocks.heicTo.mockResolvedValueOnce(new Blob(["jpeg"], { type: "image/jpeg" }));

 const result = await prepareImageForAttachment(original, 1024);

 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(mocks.heicTo).toHaveBeenCalledOnce();
 });

 it("rejects oversized HEIC dimensions before loading the decoder", async () => {
 const original = makeHeicFile({ width: 16_000, height: 4001 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "too-large",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("rejects invalid HEIC metadata before loading the decoder", async () => {
 const original = new File([new Uint8Array([1, 2, 3])], "broken.heic", {
 type: "image/heic",
 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "unreadable",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("reports unreadable when HEIC decoding fails", async () => {
 const original = makeHeicFile({
 name: "broken.heic",
 type: "image/heic",
 });
 mocks.heicTo.mockRejectedValueOnce(new Error("Invalid HEIC image"));

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "unreadable",
 });
 });

 it("rejects unsafe HEIC sources before loading the decoder", async () => {
 const original = new File(["photo"], "large.heic", { type: "image/heic" });
 Object.defineProperty(original, "size", { value: MAX_COMPRESSIBLE_SOURCE_BYTES + 1 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "too-large",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("leaves supported images untouched without loading the HEIC decoder", async () => {
 const original = makeFile(1024);

 const result = await prepareImageForAttachment(original, 2048);

 expect(result.ok && result.file).toBe(original);
 expect(result.ok && result.recompressed).toBe(false);
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });
});
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Highlight search terms from Google/DuckDuckGo/Bing referrer
(function() {
var ref = document.referrer;
var terms = [];
if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {
var url = new URL(ref);
var q = url.searchParams.get('q') || url.searchParams.get('p');
if (q) {
terms = q.split(/\s+/).filter(function(t) { return t.length > 2; });
}
}
if (terms.length === 0) return;
var style = document.createElement('style');
style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';
document.head.appendChild(style);
function highlight(node) {
if (node.nodeType === 3) { // text node
var text = node.textContent;
var found = false;
terms.forEach(function(term) {
var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\]\\]/g, '\\') + ')', 'gi');
if (regex.test(text)) {
found = true;
var frag = document.createDocumentFragment();
var parts = text.split(regex);
parts.forEach(function(part, i) {
if (i % 2 === 0) {
frag.appendChild(document.createTextNode(part));
} else {
var span = document.createElement('span');
span.className = 'userscript-highlight';
span.textContent = part;
frag.appendChild(span);
}
});
node.parentNode.replaceChild(frag, node);
}
});
} else if (node.nodeType === 1 && node.childNodes) { // element
var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];
if (!skipTags.includes(node.tagName)) {
Array.from(node.childNodes).forEach(highlight);
}
}
}
highlight(document.body);
// Re-highlight on dynamic content
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1 || node.nodeType === 3) highlight(node);
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
feat(web): safely attach HEIC photos as JPEG images#8161

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 Merged

t3dotgg
merged 7 commits into

from

Aug 25, 2026
 Merged


feat(web): safely attach HEIC photos as JPEG images
#8161
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97ca4a2

chore(web): add browser-side HEIC image decoder


mweinbach Aug 25, 2026
b977edd

feat(web): convert HEIC photo attachments to JPEG


mweinbach Aug 25, 2026
8f510c7

fix(web): bound HEIC decoding and include decoder licenses


t3dotgg Aug 25, 2026
e451843

fix(web): trust image MIME types before HEIC extensions


t3dotgg Aug 25, 2026
eaa7b1c

fix(web): allow full-resolution HEIC photo attachments


t3dotgg Aug 25, 2026
0810a80

fix(web): limit HEIC image dimensions before decoding


t3dotgg Aug 25, 2026
1a9d391

fix(web): reject unsupported HEIC image sequences


t3dotgg Aug 25, 2026

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1 change: 1 addition & 0 deletions
apps/web/package.json

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Original file line numberDiff line numberDiff line change
Expand Up@@ -34,6 +34,7 @@
 "class-variance-authority": "^0.7.1",
 "culori": "^4.0.2",
 "effect": "catalog:",
 "heic-to": "^1.5.2",
 "jose": "catalog:",
 "jsonc-parser": "3.3.1",
 "jszip": "3.10.1",
Expand Down

22 changes: 16 additions & 6 deletions
apps/web/src/components/chat/ChatComposer.tsx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -73,7 +73,11 @@ import {
 type ComposerTaskStep,
 type ComposerTasksProgress,
} from "./ComposerTasksBadge";
import { compressImageForStash, compressImageToByteLimit } from "../../lib/imageCompression";
import {
 compressImageForStash,
 isHeicImageFile,
 prepareImageForAttachment,
} from "../../lib/imageCompression";
import {
 releaseAttachmentUpload,
 retryAttachmentUpload,
Expand DownExpand Up@@ -2537,12 +2541,13 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 const acceptedFiles: File[] = [];
 let error: string | null = null;
 for (const file of files) {
 if (!file.type.startsWith("image/")) {
 const isHeicImage = isHeicImageFile(file);
Comment thread
macroscopeapp[bot] marked this conversation as resolved.

 if (!file.type.startsWith("image/") && !isHeicImage) {
 error = `Unsupported file type for '${file.name}'. Please attach image files only.`;
 continue;
 }
 if (!isProviderSendTurnSupportedImageMimeType(file.type)) {
 error = `'${file.name}' is not a supported image type. Attach GIF, JPEG, PNG, or WebP images.`;
 if (!isHeicImage && !isProviderSendTurnSupportedImageMimeType(file.type)) {
 error = `'${file.name}' is not a supported image type. Attach GIF, HEIC, HEIF, JPEG, PNG, or WebP images.`;
 continue;
 }
 if (reservedCount >= PROVIDER_SEND_TURN_MAX_ATTACHMENTS) {
Expand All@@ -2562,7 +2567,10 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 for (const file of acceptedFiles) {
 // Images over the wire cap are downscaled to fit rather than
 // refused; files already within it pass through byte-for-byte.
 const compressed = await compressImageToByteLimit(file, PROVIDER_SEND_TURN_MAX_IMAGE_BYTES);
 const compressed = await prepareImageForAttachment(
 file,
 PROVIDER_SEND_TURN_MAX_IMAGE_BYTES,
 );
 if (!compressed.ok) {
 compressionError =
 compressed.reason === "unreadable"
Expand DownExpand Up@@ -2615,7 +2623,9 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 const onComposerPaste = (event: React.ClipboardEvent<HTMLElement>) => {
 const files = Array.from(event.clipboardData.files);
 if (files.length === 0) return;
 const imageFiles = files.filter((file) => file.type.startsWith("image/"));
 const imageFiles = files.filter(
 (file) => file.type.startsWith("image/") || isHeicImageFile(file),
 );
 if (imageFiles.length === 0) return;
 event.preventDefault();
 void addComposerImages(imageFiles);
Expand Down

195 changes: 195 additions & 0 deletions
apps/web/src/lib/imageCompression.test.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -3,10 +3,20 @@ import { afterEach, describe, expect, it, vi } from "vite-plus/test";
import {
 compressImageForStash,
 compressImageToByteLimit,
 isHeicImageFile,
 MAX_COMPRESSIBLE_SOURCE_BYTES,
 MAX_STASH_IMAGE_DATA_URL_CHARS,
 prepareImageForAttachment,
} from "./imageCompression";

const mocks = vi.hoisted(() => ({
 heicTo: vi.fn(),
}));

vi.mock("heic-to/csp", () => ({
 heicTo: mocks.heicTo,
}));

/**
 * jsdom has no real canvas/codec, so the re-encode path is exercised with
 * stubbed `createImageBitmap` + `OffscreenCanvas`. The encoder stub returns a
Expand All@@ -22,6 +32,45 @@ function makeFile(sizeBytes: number, type = "image/png"): File {
 return new File([new Uint8Array(sizeBytes).fill(7)], "shot.png", { type });
}

function makeHeicFile(options?: {
 name?: string;
 type?: string;
 width?: number;
 height?: number;
 lastModified?: number;
}): File {
 const encoder = new TextEncoder();
 const makeBox = (name: string, ...contents: Uint8Array[]) => {
 const bytes = new Uint8Array(8 + contents.reduce((size, content) => size + content.length, 0));
 new DataView(bytes.buffer).setUint32(0, bytes.length);
 bytes.set(encoder.encode(name), 4);
 let offset = 8;
 for (const content of contents) {
 bytes.set(content, offset);
 offset += content.length;
 }
 return bytes;
 };

 const dimensions = new Uint8Array(12);
 const view = new DataView(dimensions.buffer);
 view.setUint32(4, options?.width ?? 4000);
 view.setUint32(8, options?.height ?? 3000);
 const properties = makeBox("iprp", makeBox("ipco", makeBox("ispe", dimensions)));

 return new File(
 [
 makeBox("ftyp", encoder.encode("heic"), new Uint8Array(4)),
 makeBox("meta", new Uint8Array(4), properties),
 ],
 options?.name ?? "photo.heic",
 {
 type: options?.type ?? "image/heic",
 ...(options?.lastModified !== undefined ? { lastModified: options.lastModified } : {}),
 },
 );
}

/**
 * Installs a fake bitmap + canvas whose encoded size follows `sizeForQuality`.
 * `supportsWebp: false` makes `convertToBlob` hand back a differently-typed
Expand DownExpand Up@@ -63,6 +112,7 @@ function stubCanvasPipeline(
}

afterEach(() => {
 mocks.heicTo.mockReset();
 vi.unstubAllGlobals();
 globalThis.createImageBitmap = originalCreateImageBitmap;
 globalThis.OffscreenCanvas = originalOffscreenCanvas;
Expand DownExpand Up@@ -251,3 +301,148 @@ describe("compressImageForStash", () => {
 expect(smallestRequested).toBeLessThan(800);
 });
});

describe("HEIC attachment preparation", () => {
 it("recognizes HEIC and HEIF MIME types and case-insensitive file extensions", () => {
 expect(isHeicImageFile({ name: "photo.bin", type: "image/heic" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.bin", type: "image/heif" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.heic", type: "image/heic-sequence" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heif", type: "image/heif-sequence" })).toBe(false);
 expect(isHeicImageFile({ name: "IMG_1234.HEIC", type: "" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.heif", type: "application/octet-stream" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.png", type: "image/png" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heic", type: "image/png" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heif", type: "image/jpeg" })).toBe(false);
 });

 it("converts a HEIC photo with a missing MIME type into a named JPEG", async () => {
 const original = makeHeicFile({
 name: "IMG_1234.HEIC",
 type: "",
 lastModified: 123,
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array([4, 5, 6, 7])], { type: "image/jpeg" }),
 );

 const result = await prepareImageForAttachment(original, 1024);

 expect(mocks.heicTo).toHaveBeenCalledWith({
 blob: original,
 type: "image/jpeg",
 quality: 0.92,
 });
 expect(result.ok && result.file.name).toBe("IMG_1234.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBe(4);
 expect(result.ok && result.file.lastModified).toBe(123);
 expect(result.ok && result.recompressed).toBe(true);
 });

 it("keeps oversized converted photos in JPEG format while shrinking them", async () => {
 const original = makeHeicFile({
 name: "photo.heif",
 type: "image/heif",
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array(2_000_000)], { type: "image/jpeg" }),
 );
 const { fillRect } = stubCanvasPipeline(() => 200_000);

 const result = await prepareImageForAttachment(original, 1_000_000);

 expect(result.ok && result.file.name).toBe("photo.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBeLessThanOrEqual(1_000_000);
 expect(fillRect).toHaveBeenCalled();
 });

 it("compresses JPEG intermediates above the source safety ceiling", async () => {
 const original = makeHeicFile({
 name: "large.heic",
 type: "image/heic",
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array(MAX_COMPRESSIBLE_SOURCE_BYTES + 1)], {
 type: "image/jpeg",
 }),
 );
 const { close } = stubCanvasPipeline(() => 200_000);

 const result = await prepareImageForAttachment(original, 1_000_000);

 expect(result.ok && result.file.name).toBe("large.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBeLessThanOrEqual(1_000_000);
 expect(close).toHaveBeenCalled();
 });

 it.each([
 { label: "24 MP", width: 5712, height: 4284 },
 { label: "48 MP", width: 8064, height: 6048 },
 ])("accepts $label HEIC photos", async ({ width, height }) => {
 const original = makeHeicFile({ width, height });
 mocks.heicTo.mockResolvedValueOnce(new Blob(["jpeg"], { type: "image/jpeg" }));

 const result = await prepareImageForAttachment(original, 1024);

 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(mocks.heicTo).toHaveBeenCalledOnce();
 });

 it("rejects oversized HEIC dimensions before loading the decoder", async () => {
 const original = makeHeicFile({ width: 16_000, height: 4001 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "too-large",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("rejects invalid HEIC metadata before loading the decoder", async () => {
 const original = new File([new Uint8Array([1, 2, 3])], "broken.heic", {
 type: "image/heic",
 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "unreadable",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("reports unreadable when HEIC decoding fails", async () => {
 const original = makeHeicFile({
 name: "broken.heic",
 type: "image/heic",
 });
 mocks.heicTo.mockRejectedValueOnce(new Error("Invalid HEIC image"));

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "unreadable",
 });
 });

 it("rejects unsafe HEIC sources before loading the decoder", async () => {
 const original = new File(["photo"], "large.heic", { type: "image/heic" });
 Object.defineProperty(original, "size", { value: MAX_COMPRESSIBLE_SOURCE_BYTES + 1 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "too-large",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("leaves supported images untouched without loading the HEIC decoder", async () => {
 const original = makeFile(1024);

 const result = await prepareImageForAttachment(original, 2048);

 expect(result.ok && result.file).toBe(original);
 expect(result.ok && result.recompressed).toBe(false);
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });
});
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Strip utm_, fbclid, gclid, etc. from all links on page
(function() {
var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
'ref', 'ref_src', 'source', 'medium', 'campaign'];
function cleanUrl(url) {
try {
var u = new URL(url, window.location.origin);
var changed = false;
trackingParams.forEach(function(p) {
if (u.searchParams.has(p)) {
u.searchParams.delete(p);
changed = true;
}
});
return changed ? u.toString() : url;
} catch (e) {
return url;
}
}
function cleanLinks() {
document.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
cleanLinks();
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1) {
if (node.tagName === 'A') cleanLinks();
node.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

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feat(web): safely attach HEIC photos as JPEG images#8161

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 Merged

t3dotgg
merged 7 commits into

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Aug 25, 2026
 Merged


feat(web): safely attach HEIC photos as JPEG images
#8161
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97ca4a2

chore(web): add browser-side HEIC image decoder


mweinbach Aug 25, 2026
b977edd

feat(web): convert HEIC photo attachments to JPEG


mweinbach Aug 25, 2026
8f510c7

fix(web): bound HEIC decoding and include decoder licenses


t3dotgg Aug 25, 2026
e451843

fix(web): trust image MIME types before HEIC extensions


t3dotgg Aug 25, 2026
eaa7b1c

fix(web): allow full-resolution HEIC photo attachments


t3dotgg Aug 25, 2026
0810a80

fix(web): limit HEIC image dimensions before decoding


t3dotgg Aug 25, 2026
1a9d391

fix(web): reject unsupported HEIC image sequences


t3dotgg Aug 25, 2026

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1 change: 1 addition & 0 deletions
apps/web/package.json

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Original file line numberDiff line numberDiff line change
Expand Up@@ -34,6 +34,7 @@
 "class-variance-authority": "^0.7.1",
 "culori": "^4.0.2",
 "effect": "catalog:",
 "heic-to": "^1.5.2",
 "jose": "catalog:",
 "jsonc-parser": "3.3.1",
 "jszip": "3.10.1",
Expand Down

22 changes: 16 additions & 6 deletions
apps/web/src/components/chat/ChatComposer.tsx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -73,7 +73,11 @@ import {
 type ComposerTaskStep,
 type ComposerTasksProgress,
} from "./ComposerTasksBadge";
import { compressImageForStash, compressImageToByteLimit } from "../../lib/imageCompression";
import {
 compressImageForStash,
 isHeicImageFile,
 prepareImageForAttachment,
} from "../../lib/imageCompression";
import {
 releaseAttachmentUpload,
 retryAttachmentUpload,
Expand DownExpand Up@@ -2537,12 +2541,13 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 const acceptedFiles: File[] = [];
 let error: string | null = null;
 for (const file of files) {
 if (!file.type.startsWith("image/")) {
 const isHeicImage = isHeicImageFile(file);
Comment thread
macroscopeapp[bot] marked this conversation as resolved.

 if (!file.type.startsWith("image/") && !isHeicImage) {
 error = `Unsupported file type for '${file.name}'. Please attach image files only.`;
 continue;
 }
 if (!isProviderSendTurnSupportedImageMimeType(file.type)) {
 error = `'${file.name}' is not a supported image type. Attach GIF, JPEG, PNG, or WebP images.`;
 if (!isHeicImage && !isProviderSendTurnSupportedImageMimeType(file.type)) {
 error = `'${file.name}' is not a supported image type. Attach GIF, HEIC, HEIF, JPEG, PNG, or WebP images.`;
 continue;
 }
 if (reservedCount >= PROVIDER_SEND_TURN_MAX_ATTACHMENTS) {
Expand All@@ -2562,7 +2567,10 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 for (const file of acceptedFiles) {
 // Images over the wire cap are downscaled to fit rather than
 // refused; files already within it pass through byte-for-byte.
 const compressed = await compressImageToByteLimit(file, PROVIDER_SEND_TURN_MAX_IMAGE_BYTES);
 const compressed = await prepareImageForAttachment(
 file,
 PROVIDER_SEND_TURN_MAX_IMAGE_BYTES,
 );
 if (!compressed.ok) {
 compressionError =
 compressed.reason === "unreadable"
Expand DownExpand Up@@ -2615,7 +2623,9 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 const onComposerPaste = (event: React.ClipboardEvent<HTMLElement>) => {
 const files = Array.from(event.clipboardData.files);
 if (files.length === 0) return;
 const imageFiles = files.filter((file) => file.type.startsWith("image/"));
 const imageFiles = files.filter(
 (file) => file.type.startsWith("image/") || isHeicImageFile(file),
 );
 if (imageFiles.length === 0) return;
 event.preventDefault();
 void addComposerImages(imageFiles);
Expand Down

195 changes: 195 additions & 0 deletions
apps/web/src/lib/imageCompression.test.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -3,10 +3,20 @@ import { afterEach, describe, expect, it, vi } from "vite-plus/test";
import {
 compressImageForStash,
 compressImageToByteLimit,
 isHeicImageFile,
 MAX_COMPRESSIBLE_SOURCE_BYTES,
 MAX_STASH_IMAGE_DATA_URL_CHARS,
 prepareImageForAttachment,
} from "./imageCompression";

const mocks = vi.hoisted(() => ({
 heicTo: vi.fn(),
}));

vi.mock("heic-to/csp", () => ({
 heicTo: mocks.heicTo,
}));

/**
 * jsdom has no real canvas/codec, so the re-encode path is exercised with
 * stubbed `createImageBitmap` + `OffscreenCanvas`. The encoder stub returns a
Expand All@@ -22,6 +32,45 @@ function makeFile(sizeBytes: number, type = "image/png"): File {
 return new File([new Uint8Array(sizeBytes).fill(7)], "shot.png", { type });
}

function makeHeicFile(options?: {
 name?: string;
 type?: string;
 width?: number;
 height?: number;
 lastModified?: number;
}): File {
 const encoder = new TextEncoder();
 const makeBox = (name: string, ...contents: Uint8Array[]) => {
 const bytes = new Uint8Array(8 + contents.reduce((size, content) => size + content.length, 0));
 new DataView(bytes.buffer).setUint32(0, bytes.length);
 bytes.set(encoder.encode(name), 4);
 let offset = 8;
 for (const content of contents) {
 bytes.set(content, offset);
 offset += content.length;
 }
 return bytes;
 };

 const dimensions = new Uint8Array(12);
 const view = new DataView(dimensions.buffer);
 view.setUint32(4, options?.width ?? 4000);
 view.setUint32(8, options?.height ?? 3000);
 const properties = makeBox("iprp", makeBox("ipco", makeBox("ispe", dimensions)));

 return new File(
 [
 makeBox("ftyp", encoder.encode("heic"), new Uint8Array(4)),
 makeBox("meta", new Uint8Array(4), properties),
 ],
 options?.name ?? "photo.heic",
 {
 type: options?.type ?? "image/heic",
 ...(options?.lastModified !== undefined ? { lastModified: options.lastModified } : {}),
 },
 );
}

/**
 * Installs a fake bitmap + canvas whose encoded size follows `sizeForQuality`.
 * `supportsWebp: false` makes `convertToBlob` hand back a differently-typed
Expand DownExpand Up@@ -63,6 +112,7 @@ function stubCanvasPipeline(
}

afterEach(() => {
 mocks.heicTo.mockReset();
 vi.unstubAllGlobals();
 globalThis.createImageBitmap = originalCreateImageBitmap;
 globalThis.OffscreenCanvas = originalOffscreenCanvas;
Expand DownExpand Up@@ -251,3 +301,148 @@ describe("compressImageForStash", () => {
 expect(smallestRequested).toBeLessThan(800);
 });
});

describe("HEIC attachment preparation", () => {
 it("recognizes HEIC and HEIF MIME types and case-insensitive file extensions", () => {
 expect(isHeicImageFile({ name: "photo.bin", type: "image/heic" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.bin", type: "image/heif" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.heic", type: "image/heic-sequence" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heif", type: "image/heif-sequence" })).toBe(false);
 expect(isHeicImageFile({ name: "IMG_1234.HEIC", type: "" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.heif", type: "application/octet-stream" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.png", type: "image/png" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heic", type: "image/png" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heif", type: "image/jpeg" })).toBe(false);
 });

 it("converts a HEIC photo with a missing MIME type into a named JPEG", async () => {
 const original = makeHeicFile({
 name: "IMG_1234.HEIC",
 type: "",
 lastModified: 123,
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array([4, 5, 6, 7])], { type: "image/jpeg" }),
 );

 const result = await prepareImageForAttachment(original, 1024);

 expect(mocks.heicTo).toHaveBeenCalledWith({
 blob: original,
 type: "image/jpeg",
 quality: 0.92,
 });
 expect(result.ok && result.file.name).toBe("IMG_1234.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBe(4);
 expect(result.ok && result.file.lastModified).toBe(123);
 expect(result.ok && result.recompressed).toBe(true);
 });

 it("keeps oversized converted photos in JPEG format while shrinking them", async () => {
 const original = makeHeicFile({
 name: "photo.heif",
 type: "image/heif",
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array(2_000_000)], { type: "image/jpeg" }),
 );
 const { fillRect } = stubCanvasPipeline(() => 200_000);

 const result = await prepareImageForAttachment(original, 1_000_000);

 expect(result.ok && result.file.name).toBe("photo.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBeLessThanOrEqual(1_000_000);
 expect(fillRect).toHaveBeenCalled();
 });

 it("compresses JPEG intermediates above the source safety ceiling", async () => {
 const original = makeHeicFile({
 name: "large.heic",
 type: "image/heic",
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array(MAX_COMPRESSIBLE_SOURCE_BYTES + 1)], {
 type: "image/jpeg",
 }),
 );
 const { close } = stubCanvasPipeline(() => 200_000);

 const result = await prepareImageForAttachment(original, 1_000_000);

 expect(result.ok && result.file.name).toBe("large.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBeLessThanOrEqual(1_000_000);
 expect(close).toHaveBeenCalled();
 });

 it.each([
 { label: "24 MP", width: 5712, height: 4284 },
 { label: "48 MP", width: 8064, height: 6048 },
 ])("accepts $label HEIC photos", async ({ width, height }) => {
 const original = makeHeicFile({ width, height });
 mocks.heicTo.mockResolvedValueOnce(new Blob(["jpeg"], { type: "image/jpeg" }));

 const result = await prepareImageForAttachment(original, 1024);

 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(mocks.heicTo).toHaveBeenCalledOnce();
 });

 it("rejects oversized HEIC dimensions before loading the decoder", async () => {
 const original = makeHeicFile({ width: 16_000, height: 4001 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "too-large",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("rejects invalid HEIC metadata before loading the decoder", async () => {
 const original = new File([new Uint8Array([1, 2, 3])], "broken.heic", {
 type: "image/heic",
 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "unreadable",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("reports unreadable when HEIC decoding fails", async () => {
 const original = makeHeicFile({
 name: "broken.heic",
 type: "image/heic",
 });
 mocks.heicTo.mockRejectedValueOnce(new Error("Invalid HEIC image"));

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "unreadable",
 });
 });

 it("rejects unsafe HEIC sources before loading the decoder", async () => {
 const original = new File(["photo"], "large.heic", { type: "image/heic" });
 Object.defineProperty(original, "size", { value: MAX_COMPRESSIBLE_SOURCE_BYTES + 1 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "too-large",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("leaves supported images untouched without loading the HEIC decoder", async () => {
 const original = makeFile(1024);

 const result = await prepareImageForAttachment(original, 2048);

 expect(result.ok && result.file).toBe(original);
 expect(result.ok && result.recompressed).toBe(false);
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });
});
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
(function() {
function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
if (btn && !btn.classList.contains('activated')) {
btn.click();
}
}
// Try immediately
tryTheater();
// Try after navigation (SPA)
var lastUrl = location.href;
setInterval(function() {
if (location.href !== lastUrl) {
lastUrl = location.href;
setTimeout(tryTheater, 500);
}
}, 1000);
// Also try on player load
var observer = new MutationObserver(tryTheater);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
feat(web): safely attach HEIC photos as JPEG images#8161

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Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

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Sign in
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 Merged

t3dotgg
merged 7 commits into

from

Aug 25, 2026
 Merged


feat(web): safely attach HEIC photos as JPEG images
#8161
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97ca4a2

chore(web): add browser-side HEIC image decoder


mweinbach Aug 25, 2026
b977edd

feat(web): convert HEIC photo attachments to JPEG


mweinbach Aug 25, 2026
8f510c7

fix(web): bound HEIC decoding and include decoder licenses


t3dotgg Aug 25, 2026
e451843

fix(web): trust image MIME types before HEIC extensions


t3dotgg Aug 25, 2026
eaa7b1c

fix(web): allow full-resolution HEIC photo attachments


t3dotgg Aug 25, 2026
0810a80

fix(web): limit HEIC image dimensions before decoding


t3dotgg Aug 25, 2026
1a9d391

fix(web): reject unsupported HEIC image sequences


t3dotgg Aug 25, 2026

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1 change: 1 addition & 0 deletions
apps/web/package.json

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Original file line numberDiff line numberDiff line change
Expand Up@@ -34,6 +34,7 @@
 "class-variance-authority": "^0.7.1",
 "culori": "^4.0.2",
 "effect": "catalog:",
 "heic-to": "^1.5.2",
 "jose": "catalog:",
 "jsonc-parser": "3.3.1",
 "jszip": "3.10.1",
Expand Down

22 changes: 16 additions & 6 deletions
apps/web/src/components/chat/ChatComposer.tsx

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -73,7 +73,11 @@ import {
 type ComposerTaskStep,
 type ComposerTasksProgress,
} from "./ComposerTasksBadge";
import { compressImageForStash, compressImageToByteLimit } from "../../lib/imageCompression";
import {
 compressImageForStash,
 isHeicImageFile,
 prepareImageForAttachment,
} from "../../lib/imageCompression";
import {
 releaseAttachmentUpload,
 retryAttachmentUpload,
Expand DownExpand Up@@ -2537,12 +2541,13 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 const acceptedFiles: File[] = [];
 let error: string | null = null;
 for (const file of files) {
 if (!file.type.startsWith("image/")) {
 const isHeicImage = isHeicImageFile(file);
Comment thread
macroscopeapp[bot] marked this conversation as resolved.

 if (!file.type.startsWith("image/") && !isHeicImage) {
 error = `Unsupported file type for '${file.name}'. Please attach image files only.`;
 continue;
 }
 if (!isProviderSendTurnSupportedImageMimeType(file.type)) {
 error = `'${file.name}' is not a supported image type. Attach GIF, JPEG, PNG, or WebP images.`;
 if (!isHeicImage && !isProviderSendTurnSupportedImageMimeType(file.type)) {
 error = `'${file.name}' is not a supported image type. Attach GIF, HEIC, HEIF, JPEG, PNG, or WebP images.`;
 continue;
 }
 if (reservedCount >= PROVIDER_SEND_TURN_MAX_ATTACHMENTS) {
Expand All@@ -2562,7 +2567,10 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 for (const file of acceptedFiles) {
 // Images over the wire cap are downscaled to fit rather than
 // refused; files already within it pass through byte-for-byte.
 const compressed = await compressImageToByteLimit(file, PROVIDER_SEND_TURN_MAX_IMAGE_BYTES);
 const compressed = await prepareImageForAttachment(
 file,
 PROVIDER_SEND_TURN_MAX_IMAGE_BYTES,
 );
 if (!compressed.ok) {
 compressionError =
 compressed.reason === "unreadable"
Expand DownExpand Up@@ -2615,7 +2623,9 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 const onComposerPaste = (event: React.ClipboardEvent<HTMLElement>) => {
 const files = Array.from(event.clipboardData.files);
 if (files.length === 0) return;
 const imageFiles = files.filter((file) => file.type.startsWith("image/"));
 const imageFiles = files.filter(
 (file) => file.type.startsWith("image/") || isHeicImageFile(file),
 );
 if (imageFiles.length === 0) return;
 event.preventDefault();
 void addComposerImages(imageFiles);
Expand Down

195 changes: 195 additions & 0 deletions
apps/web/src/lib/imageCompression.test.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -3,10 +3,20 @@ import { afterEach, describe, expect, it, vi } from "vite-plus/test";
import {
 compressImageForStash,
 compressImageToByteLimit,
 isHeicImageFile,
 MAX_COMPRESSIBLE_SOURCE_BYTES,
 MAX_STASH_IMAGE_DATA_URL_CHARS,
 prepareImageForAttachment,
} from "./imageCompression";

const mocks = vi.hoisted(() => ({
 heicTo: vi.fn(),
}));

vi.mock("heic-to/csp", () => ({
 heicTo: mocks.heicTo,
}));

/**
 * jsdom has no real canvas/codec, so the re-encode path is exercised with
 * stubbed `createImageBitmap` + `OffscreenCanvas`. The encoder stub returns a
Expand All@@ -22,6 +32,45 @@ function makeFile(sizeBytes: number, type = "image/png"): File {
 return new File([new Uint8Array(sizeBytes).fill(7)], "shot.png", { type });
}

function makeHeicFile(options?: {
 name?: string;
 type?: string;
 width?: number;
 height?: number;
 lastModified?: number;
}): File {
 const encoder = new TextEncoder();
 const makeBox = (name: string, ...contents: Uint8Array[]) => {
 const bytes = new Uint8Array(8 + contents.reduce((size, content) => size + content.length, 0));
 new DataView(bytes.buffer).setUint32(0, bytes.length);
 bytes.set(encoder.encode(name), 4);
 let offset = 8;
 for (const content of contents) {
 bytes.set(content, offset);
 offset += content.length;
 }
 return bytes;
 };

 const dimensions = new Uint8Array(12);
 const view = new DataView(dimensions.buffer);
 view.setUint32(4, options?.width ?? 4000);
 view.setUint32(8, options?.height ?? 3000);
 const properties = makeBox("iprp", makeBox("ipco", makeBox("ispe", dimensions)));

 return new File(
 [
 makeBox("ftyp", encoder.encode("heic"), new Uint8Array(4)),
 makeBox("meta", new Uint8Array(4), properties),
 ],
 options?.name ?? "photo.heic",
 {
 type: options?.type ?? "image/heic",
 ...(options?.lastModified !== undefined ? { lastModified: options.lastModified } : {}),
 },
 );
}

/**
 * Installs a fake bitmap + canvas whose encoded size follows `sizeForQuality`.
 * `supportsWebp: false` makes `convertToBlob` hand back a differently-typed
Expand DownExpand Up@@ -63,6 +112,7 @@ function stubCanvasPipeline(
}

afterEach(() => {
 mocks.heicTo.mockReset();
 vi.unstubAllGlobals();
 globalThis.createImageBitmap = originalCreateImageBitmap;
 globalThis.OffscreenCanvas = originalOffscreenCanvas;
Expand DownExpand Up@@ -251,3 +301,148 @@ describe("compressImageForStash", () => {
 expect(smallestRequested).toBeLessThan(800);
 });
});

describe("HEIC attachment preparation", () => {
 it("recognizes HEIC and HEIF MIME types and case-insensitive file extensions", () => {
 expect(isHeicImageFile({ name: "photo.bin", type: "image/heic" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.bin", type: "image/heif" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.heic", type: "image/heic-sequence" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heif", type: "image/heif-sequence" })).toBe(false);
 expect(isHeicImageFile({ name: "IMG_1234.HEIC", type: "" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.heif", type: "application/octet-stream" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.png", type: "image/png" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heic", type: "image/png" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heif", type: "image/jpeg" })).toBe(false);
 });

 it("converts a HEIC photo with a missing MIME type into a named JPEG", async () => {
 const original = makeHeicFile({
 name: "IMG_1234.HEIC",
 type: "",
 lastModified: 123,
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array([4, 5, 6, 7])], { type: "image/jpeg" }),
 );

 const result = await prepareImageForAttachment(original, 1024);

 expect(mocks.heicTo).toHaveBeenCalledWith({
 blob: original,
 type: "image/jpeg",
 quality: 0.92,
 });
 expect(result.ok && result.file.name).toBe("IMG_1234.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBe(4);
 expect(result.ok && result.file.lastModified).toBe(123);
 expect(result.ok && result.recompressed).toBe(true);
 });

 it("keeps oversized converted photos in JPEG format while shrinking them", async () => {
 const original = makeHeicFile({
 name: "photo.heif",
 type: "image/heif",
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array(2_000_000)], { type: "image/jpeg" }),
 );
 const { fillRect } = stubCanvasPipeline(() => 200_000);

 const result = await prepareImageForAttachment(original, 1_000_000);

 expect(result.ok && result.file.name).toBe("photo.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBeLessThanOrEqual(1_000_000);
 expect(fillRect).toHaveBeenCalled();
 });

 it("compresses JPEG intermediates above the source safety ceiling", async () => {
 const original = makeHeicFile({
 name: "large.heic",
 type: "image/heic",
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array(MAX_COMPRESSIBLE_SOURCE_BYTES + 1)], {
 type: "image/jpeg",
 }),
 );
 const { close } = stubCanvasPipeline(() => 200_000);

 const result = await prepareImageForAttachment(original, 1_000_000);

 expect(result.ok && result.file.name).toBe("large.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBeLessThanOrEqual(1_000_000);
 expect(close).toHaveBeenCalled();
 });

 it.each([
 { label: "24 MP", width: 5712, height: 4284 },
 { label: "48 MP", width: 8064, height: 6048 },
 ])("accepts $label HEIC photos", async ({ width, height }) => {
 const original = makeHeicFile({ width, height });
 mocks.heicTo.mockResolvedValueOnce(new Blob(["jpeg"], { type: "image/jpeg" }));

 const result = await prepareImageForAttachment(original, 1024);

 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(mocks.heicTo).toHaveBeenCalledOnce();
 });

 it("rejects oversized HEIC dimensions before loading the decoder", async () => {
 const original = makeHeicFile({ width: 16_000, height: 4001 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "too-large",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("rejects invalid HEIC metadata before loading the decoder", async () => {
 const original = new File([new Uint8Array([1, 2, 3])], "broken.heic", {
 type: "image/heic",
 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "unreadable",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("reports unreadable when HEIC decoding fails", async () => {
 const original = makeHeicFile({
 name: "broken.heic",
 type: "image/heic",
 });
 mocks.heicTo.mockRejectedValueOnce(new Error("Invalid HEIC image"));

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "unreadable",
 });
 });

 it("rejects unsafe HEIC sources before loading the decoder", async () => {
 const original = new File(["photo"], "large.heic", { type: "image/heic" });
 Object.defineProperty(original, "size", { value: MAX_COMPRESSIBLE_SOURCE_BYTES + 1 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "too-large",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("leaves supported images untouched without loading the HEIC decoder", async () => {
 const original = makeFile(1024);

 const result = await prepareImageForAttachment(original, 2048);

 expect(result.ok && result.file).toBe(original);
 expect(result.ok && result.recompressed).toBe(false);
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });
});
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// Remove or un-stick sticky/fixed headers that block content
(function() {
function unstick() {
document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) {
if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {
el.style.position = 'static';
el.style.top = 'auto';
el.style.zIndex = 'auto';
}
});
}
unstick();
var observer = new MutationObserver(unstick);
observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });
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feat(web): safely attach HEIC photos as JPEG images#8161

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 Merged

t3dotgg
merged 7 commits into

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Aug 25, 2026
 Merged


feat(web): safely attach HEIC photos as JPEG images
#8161
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97ca4a2

chore(web): add browser-side HEIC image decoder


mweinbach Aug 25, 2026
b977edd

feat(web): convert HEIC photo attachments to JPEG


mweinbach Aug 25, 2026
8f510c7

fix(web): bound HEIC decoding and include decoder licenses


t3dotgg Aug 25, 2026
e451843

fix(web): trust image MIME types before HEIC extensions


t3dotgg Aug 25, 2026
eaa7b1c

fix(web): allow full-resolution HEIC photo attachments


t3dotgg Aug 25, 2026
0810a80

fix(web): limit HEIC image dimensions before decoding


t3dotgg Aug 25, 2026
1a9d391

fix(web): reject unsupported HEIC image sequences


t3dotgg Aug 25, 2026

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1 change: 1 addition & 0 deletions
apps/web/package.json

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Original file line numberDiff line numberDiff line change
Expand Up@@ -34,6 +34,7 @@
 "class-variance-authority": "^0.7.1",
 "culori": "^4.0.2",
 "effect": "catalog:",
 "heic-to": "^1.5.2",
 "jose": "catalog:",
 "jsonc-parser": "3.3.1",
 "jszip": "3.10.1",
Expand Down

22 changes: 16 additions & 6 deletions
apps/web/src/components/chat/ChatComposer.tsx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -73,7 +73,11 @@ import {
 type ComposerTaskStep,
 type ComposerTasksProgress,
} from "./ComposerTasksBadge";
import { compressImageForStash, compressImageToByteLimit } from "../../lib/imageCompression";
import {
 compressImageForStash,
 isHeicImageFile,
 prepareImageForAttachment,
} from "../../lib/imageCompression";
import {
 releaseAttachmentUpload,
 retryAttachmentUpload,
Expand DownExpand Up@@ -2537,12 +2541,13 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 const acceptedFiles: File[] = [];
 let error: string | null = null;
 for (const file of files) {
 if (!file.type.startsWith("image/")) {
 const isHeicImage = isHeicImageFile(file);
Comment thread
macroscopeapp[bot] marked this conversation as resolved.

 if (!file.type.startsWith("image/") && !isHeicImage) {
 error = `Unsupported file type for '${file.name}'. Please attach image files only.`;
 continue;
 }
 if (!isProviderSendTurnSupportedImageMimeType(file.type)) {
 error = `'${file.name}' is not a supported image type. Attach GIF, JPEG, PNG, or WebP images.`;
 if (!isHeicImage && !isProviderSendTurnSupportedImageMimeType(file.type)) {
 error = `'${file.name}' is not a supported image type. Attach GIF, HEIC, HEIF, JPEG, PNG, or WebP images.`;
 continue;
 }
 if (reservedCount >= PROVIDER_SEND_TURN_MAX_ATTACHMENTS) {
Expand All@@ -2562,7 +2567,10 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 for (const file of acceptedFiles) {
 // Images over the wire cap are downscaled to fit rather than
 // refused; files already within it pass through byte-for-byte.
 const compressed = await compressImageToByteLimit(file, PROVIDER_SEND_TURN_MAX_IMAGE_BYTES);
 const compressed = await prepareImageForAttachment(
 file,
 PROVIDER_SEND_TURN_MAX_IMAGE_BYTES,
 );
 if (!compressed.ok) {
 compressionError =
 compressed.reason === "unreadable"
Expand DownExpand Up@@ -2615,7 +2623,9 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 const onComposerPaste = (event: React.ClipboardEvent<HTMLElement>) => {
 const files = Array.from(event.clipboardData.files);
 if (files.length === 0) return;
 const imageFiles = files.filter((file) => file.type.startsWith("image/"));
 const imageFiles = files.filter(
 (file) => file.type.startsWith("image/") || isHeicImageFile(file),
 );
 if (imageFiles.length === 0) return;
 event.preventDefault();
 void addComposerImages(imageFiles);
Expand Down

195 changes: 195 additions & 0 deletions
apps/web/src/lib/imageCompression.test.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -3,10 +3,20 @@ import { afterEach, describe, expect, it, vi } from "vite-plus/test";
import {
 compressImageForStash,
 compressImageToByteLimit,
 isHeicImageFile,
 MAX_COMPRESSIBLE_SOURCE_BYTES,
 MAX_STASH_IMAGE_DATA_URL_CHARS,
 prepareImageForAttachment,
} from "./imageCompression";

const mocks = vi.hoisted(() => ({
 heicTo: vi.fn(),
}));

vi.mock("heic-to/csp", () => ({
 heicTo: mocks.heicTo,
}));

/**
 * jsdom has no real canvas/codec, so the re-encode path is exercised with
 * stubbed `createImageBitmap` + `OffscreenCanvas`. The encoder stub returns a
Expand All@@ -22,6 +32,45 @@ function makeFile(sizeBytes: number, type = "image/png"): File {
 return new File([new Uint8Array(sizeBytes).fill(7)], "shot.png", { type });
}

function makeHeicFile(options?: {
 name?: string;
 type?: string;
 width?: number;
 height?: number;
 lastModified?: number;
}): File {
 const encoder = new TextEncoder();
 const makeBox = (name: string, ...contents: Uint8Array[]) => {
 const bytes = new Uint8Array(8 + contents.reduce((size, content) => size + content.length, 0));
 new DataView(bytes.buffer).setUint32(0, bytes.length);
 bytes.set(encoder.encode(name), 4);
 let offset = 8;
 for (const content of contents) {
 bytes.set(content, offset);
 offset += content.length;
 }
 return bytes;
 };

 const dimensions = new Uint8Array(12);
 const view = new DataView(dimensions.buffer);
 view.setUint32(4, options?.width ?? 4000);
 view.setUint32(8, options?.height ?? 3000);
 const properties = makeBox("iprp", makeBox("ipco", makeBox("ispe", dimensions)));

 return new File(
 [
 makeBox("ftyp", encoder.encode("heic"), new Uint8Array(4)),
 makeBox("meta", new Uint8Array(4), properties),
 ],
 options?.name ?? "photo.heic",
 {
 type: options?.type ?? "image/heic",
 ...(options?.lastModified !== undefined ? { lastModified: options.lastModified } : {}),
 },
 );
}

/**
 * Installs a fake bitmap + canvas whose encoded size follows `sizeForQuality`.
 * `supportsWebp: false` makes `convertToBlob` hand back a differently-typed
Expand DownExpand Up@@ -63,6 +112,7 @@ function stubCanvasPipeline(
}

afterEach(() => {
 mocks.heicTo.mockReset();
 vi.unstubAllGlobals();
 globalThis.createImageBitmap = originalCreateImageBitmap;
 globalThis.OffscreenCanvas = originalOffscreenCanvas;
Expand DownExpand Up@@ -251,3 +301,148 @@ describe("compressImageForStash", () => {
 expect(smallestRequested).toBeLessThan(800);
 });
});

describe("HEIC attachment preparation", () => {
 it("recognizes HEIC and HEIF MIME types and case-insensitive file extensions", () => {
 expect(isHeicImageFile({ name: "photo.bin", type: "image/heic" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.bin", type: "image/heif" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.heic", type: "image/heic-sequence" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heif", type: "image/heif-sequence" })).toBe(false);
 expect(isHeicImageFile({ name: "IMG_1234.HEIC", type: "" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.heif", type: "application/octet-stream" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.png", type: "image/png" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heic", type: "image/png" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heif", type: "image/jpeg" })).toBe(false);
 });

 it("converts a HEIC photo with a missing MIME type into a named JPEG", async () => {
 const original = makeHeicFile({
 name: "IMG_1234.HEIC",
 type: "",
 lastModified: 123,
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array([4, 5, 6, 7])], { type: "image/jpeg" }),
 );

 const result = await prepareImageForAttachment(original, 1024);

 expect(mocks.heicTo).toHaveBeenCalledWith({
 blob: original,
 type: "image/jpeg",
 quality: 0.92,
 });
 expect(result.ok && result.file.name).toBe("IMG_1234.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBe(4);
 expect(result.ok && result.file.lastModified).toBe(123);
 expect(result.ok && result.recompressed).toBe(true);
 });

 it("keeps oversized converted photos in JPEG format while shrinking them", async () => {
 const original = makeHeicFile({
 name: "photo.heif",
 type: "image/heif",
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array(2_000_000)], { type: "image/jpeg" }),
 );
 const { fillRect } = stubCanvasPipeline(() => 200_000);

 const result = await prepareImageForAttachment(original, 1_000_000);

 expect(result.ok && result.file.name).toBe("photo.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBeLessThanOrEqual(1_000_000);
 expect(fillRect).toHaveBeenCalled();
 });

 it("compresses JPEG intermediates above the source safety ceiling", async () => {
 const original = makeHeicFile({
 name: "large.heic",
 type: "image/heic",
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array(MAX_COMPRESSIBLE_SOURCE_BYTES + 1)], {
 type: "image/jpeg",
 }),
 );
 const { close } = stubCanvasPipeline(() => 200_000);

 const result = await prepareImageForAttachment(original, 1_000_000);

 expect(result.ok && result.file.name).toBe("large.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBeLessThanOrEqual(1_000_000);
 expect(close).toHaveBeenCalled();
 });

 it.each([
 { label: "24 MP", width: 5712, height: 4284 },
 { label: "48 MP", width: 8064, height: 6048 },
 ])("accepts $label HEIC photos", async ({ width, height }) => {
 const original = makeHeicFile({ width, height });
 mocks.heicTo.mockResolvedValueOnce(new Blob(["jpeg"], { type: "image/jpeg" }));

 const result = await prepareImageForAttachment(original, 1024);

 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(mocks.heicTo).toHaveBeenCalledOnce();
 });

 it("rejects oversized HEIC dimensions before loading the decoder", async () => {
 const original = makeHeicFile({ width: 16_000, height: 4001 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "too-large",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("rejects invalid HEIC metadata before loading the decoder", async () => {
 const original = new File([new Uint8Array([1, 2, 3])], "broken.heic", {
 type: "image/heic",
 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "unreadable",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("reports unreadable when HEIC decoding fails", async () => {
 const original = makeHeicFile({
 name: "broken.heic",
 type: "image/heic",
 });
 mocks.heicTo.mockRejectedValueOnce(new Error("Invalid HEIC image"));

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "unreadable",
 });
 });

 it("rejects unsafe HEIC sources before loading the decoder", async () => {
 const original = new File(["photo"], "large.heic", { type: "image/heic" });
 Object.defineProperty(original, "size", { value: MAX_COMPRESSIBLE_SOURCE_BYTES + 1 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "too-large",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("leaves supported images untouched without loading the HEIC decoder", async () => {
 const original = makeFile(1024);

 const result = await prepareImageForAttachment(original, 2048);

 expect(result.ok && result.file).toBe(original);
 expect(result.ok && result.recompressed).toBe(false);
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });
});
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Universal Dark Mode - works on any site
(function() {
var enabled = true;
function applyDarkMode() {
if (!enabled) return;
// Create style element if it doesn't exist
var style = document.getElementById('universal-dark-mode-style');
if (!style) {
style = document.createElement('style');
style.id = 'universal-dark-mode-style';
document.head.appendChild(style);
}
// Dark mode CSS - inverts colors but preserves images/video
style.textContent = '
/* Invert everything except media */
html {
filter: invert(1) hue-rotate(180deg) !important;
background: #1a1a2e !important;
}
/* Restore images, videos, iframes, canvas */
img, video, iframe, canvas, svg, picture, [style*="background-image"] {
filter: invert(1) hue-rotate(180deg) !important;
}
/* Preserve specific elements that should not be inverted */
.no-dark-mode, .no-dark-mode *,
[data-theme="light"], [data-theme="light"],
.ace_editor, .ace_editor *,
.CodeMirror, .CodeMirror *,
.monaco-editor, .monaco-editor *,
.markdown-body pre, .markdown-body pre *,
.highlight, .highlight *,
pre code, pre code * {
filter: none !important;
}
/* Fix common UI elements */
.modal, .popup, .dropdown-menu, .tooltip, .popover {
filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
}
/* Scrollbars */
::-webkit-scrollbar { background: #1a1a2e !important; }
::-webkit-scrollbar-thumb { background: #444 !important; }
::-webkit-scrollbar-thumb:hover { background: #555 !important; }
/* Selection */
::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
';
}
function removeDarkMode() {
var style = document.getElementById('universal-dark-mode-style');
if (style) style.remove();
}
// Toggle with Alt+Shift+D
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feat(web): safely attach HEIC photos as JPEG images#8161

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t3dotgg
merged 7 commits into

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Aug 25, 2026
 Merged


feat(web): safely attach HEIC photos as JPEG images
#8161
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97ca4a2

chore(web): add browser-side HEIC image decoder


mweinbach Aug 25, 2026
b977edd

feat(web): convert HEIC photo attachments to JPEG


mweinbach Aug 25, 2026
8f510c7

fix(web): bound HEIC decoding and include decoder licenses


t3dotgg Aug 25, 2026
e451843

fix(web): trust image MIME types before HEIC extensions


t3dotgg Aug 25, 2026
eaa7b1c

fix(web): allow full-resolution HEIC photo attachments


t3dotgg Aug 25, 2026
0810a80

fix(web): limit HEIC image dimensions before decoding


t3dotgg Aug 25, 2026
1a9d391

fix(web): reject unsupported HEIC image sequences


t3dotgg Aug 25, 2026

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1 change: 1 addition & 0 deletions
apps/web/package.json

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Original file line numberDiff line numberDiff line change
Expand Up@@ -34,6 +34,7 @@
 "class-variance-authority": "^0.7.1",
 "culori": "^4.0.2",
 "effect": "catalog:",
 "heic-to": "^1.5.2",
 "jose": "catalog:",
 "jsonc-parser": "3.3.1",
 "jszip": "3.10.1",
Expand Down

22 changes: 16 additions & 6 deletions
apps/web/src/components/chat/ChatComposer.tsx

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Original file line numberDiff line numberDiff line change
Expand Up@@ -73,7 +73,11 @@ import {
 type ComposerTaskStep,
 type ComposerTasksProgress,
} from "./ComposerTasksBadge";
import { compressImageForStash, compressImageToByteLimit } from "../../lib/imageCompression";
import {
 compressImageForStash,
 isHeicImageFile,
 prepareImageForAttachment,
} from "../../lib/imageCompression";
import {
 releaseAttachmentUpload,
 retryAttachmentUpload,
Expand DownExpand Up@@ -2537,12 +2541,13 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 const acceptedFiles: File[] = [];
 let error: string | null = null;
 for (const file of files) {
 if (!file.type.startsWith("image/")) {
 const isHeicImage = isHeicImageFile(file);
Comment thread
macroscopeapp[bot] marked this conversation as resolved.

 if (!file.type.startsWith("image/") && !isHeicImage) {
 error = `Unsupported file type for '${file.name}'. Please attach image files only.`;
 continue;
 }
 if (!isProviderSendTurnSupportedImageMimeType(file.type)) {
 error = `'${file.name}' is not a supported image type. Attach GIF, JPEG, PNG, or WebP images.`;
 if (!isHeicImage && !isProviderSendTurnSupportedImageMimeType(file.type)) {
 error = `'${file.name}' is not a supported image type. Attach GIF, HEIC, HEIF, JPEG, PNG, or WebP images.`;
 continue;
 }
 if (reservedCount >= PROVIDER_SEND_TURN_MAX_ATTACHMENTS) {
Expand All@@ -2562,7 +2567,10 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 for (const file of acceptedFiles) {
 // Images over the wire cap are downscaled to fit rather than
 // refused; files already within it pass through byte-for-byte.
 const compressed = await compressImageToByteLimit(file, PROVIDER_SEND_TURN_MAX_IMAGE_BYTES);
 const compressed = await prepareImageForAttachment(
 file,
 PROVIDER_SEND_TURN_MAX_IMAGE_BYTES,
 );
 if (!compressed.ok) {
 compressionError =
 compressed.reason === "unreadable"
Expand DownExpand Up@@ -2615,7 +2623,9 @@ export const ChatComposer = memo(function ChatComposer(props: ChatComposerProps)
 const onComposerPaste = (event: React.ClipboardEvent<HTMLElement>) => {
 const files = Array.from(event.clipboardData.files);
 if (files.length === 0) return;
 const imageFiles = files.filter((file) => file.type.startsWith("image/"));
 const imageFiles = files.filter(
 (file) => file.type.startsWith("image/") || isHeicImageFile(file),
 );
 if (imageFiles.length === 0) return;
 event.preventDefault();
 void addComposerImages(imageFiles);
Expand Down

195 changes: 195 additions & 0 deletions
apps/web/src/lib/imageCompression.test.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -3,10 +3,20 @@ import { afterEach, describe, expect, it, vi } from "vite-plus/test";
import {
 compressImageForStash,
 compressImageToByteLimit,
 isHeicImageFile,
 MAX_COMPRESSIBLE_SOURCE_BYTES,
 MAX_STASH_IMAGE_DATA_URL_CHARS,
 prepareImageForAttachment,
} from "./imageCompression";

const mocks = vi.hoisted(() => ({
 heicTo: vi.fn(),
}));

vi.mock("heic-to/csp", () => ({
 heicTo: mocks.heicTo,
}));

/**
 * jsdom has no real canvas/codec, so the re-encode path is exercised with
 * stubbed `createImageBitmap` + `OffscreenCanvas`. The encoder stub returns a
Expand All@@ -22,6 +32,45 @@ function makeFile(sizeBytes: number, type = "image/png"): File {
 return new File([new Uint8Array(sizeBytes).fill(7)], "shot.png", { type });
}

function makeHeicFile(options?: {
 name?: string;
 type?: string;
 width?: number;
 height?: number;
 lastModified?: number;
}): File {
 const encoder = new TextEncoder();
 const makeBox = (name: string, ...contents: Uint8Array[]) => {
 const bytes = new Uint8Array(8 + contents.reduce((size, content) => size + content.length, 0));
 new DataView(bytes.buffer).setUint32(0, bytes.length);
 bytes.set(encoder.encode(name), 4);
 let offset = 8;
 for (const content of contents) {
 bytes.set(content, offset);
 offset += content.length;
 }
 return bytes;
 };

 const dimensions = new Uint8Array(12);
 const view = new DataView(dimensions.buffer);
 view.setUint32(4, options?.width ?? 4000);
 view.setUint32(8, options?.height ?? 3000);
 const properties = makeBox("iprp", makeBox("ipco", makeBox("ispe", dimensions)));

 return new File(
 [
 makeBox("ftyp", encoder.encode("heic"), new Uint8Array(4)),
 makeBox("meta", new Uint8Array(4), properties),
 ],
 options?.name ?? "photo.heic",
 {
 type: options?.type ?? "image/heic",
 ...(options?.lastModified !== undefined ? { lastModified: options.lastModified } : {}),
 },
 );
}

/**
 * Installs a fake bitmap + canvas whose encoded size follows `sizeForQuality`.
 * `supportsWebp: false` makes `convertToBlob` hand back a differently-typed
Expand DownExpand Up@@ -63,6 +112,7 @@ function stubCanvasPipeline(
}

afterEach(() => {
 mocks.heicTo.mockReset();
 vi.unstubAllGlobals();
 globalThis.createImageBitmap = originalCreateImageBitmap;
 globalThis.OffscreenCanvas = originalOffscreenCanvas;
Expand DownExpand Up@@ -251,3 +301,148 @@ describe("compressImageForStash", () => {
 expect(smallestRequested).toBeLessThan(800);
 });
});

describe("HEIC attachment preparation", () => {
 it("recognizes HEIC and HEIF MIME types and case-insensitive file extensions", () => {
 expect(isHeicImageFile({ name: "photo.bin", type: "image/heic" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.bin", type: "image/heif" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.heic", type: "image/heic-sequence" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heif", type: "image/heif-sequence" })).toBe(false);
 expect(isHeicImageFile({ name: "IMG_1234.HEIC", type: "" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.heif", type: "application/octet-stream" })).toBe(true);
 expect(isHeicImageFile({ name: "photo.png", type: "image/png" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heic", type: "image/png" })).toBe(false);
 expect(isHeicImageFile({ name: "photo.heif", type: "image/jpeg" })).toBe(false);
 });

 it("converts a HEIC photo with a missing MIME type into a named JPEG", async () => {
 const original = makeHeicFile({
 name: "IMG_1234.HEIC",
 type: "",
 lastModified: 123,
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array([4, 5, 6, 7])], { type: "image/jpeg" }),
 );

 const result = await prepareImageForAttachment(original, 1024);

 expect(mocks.heicTo).toHaveBeenCalledWith({
 blob: original,
 type: "image/jpeg",
 quality: 0.92,
 });
 expect(result.ok && result.file.name).toBe("IMG_1234.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBe(4);
 expect(result.ok && result.file.lastModified).toBe(123);
 expect(result.ok && result.recompressed).toBe(true);
 });

 it("keeps oversized converted photos in JPEG format while shrinking them", async () => {
 const original = makeHeicFile({
 name: "photo.heif",
 type: "image/heif",
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array(2_000_000)], { type: "image/jpeg" }),
 );
 const { fillRect } = stubCanvasPipeline(() => 200_000);

 const result = await prepareImageForAttachment(original, 1_000_000);

 expect(result.ok && result.file.name).toBe("photo.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBeLessThanOrEqual(1_000_000);
 expect(fillRect).toHaveBeenCalled();
 });

 it("compresses JPEG intermediates above the source safety ceiling", async () => {
 const original = makeHeicFile({
 name: "large.heic",
 type: "image/heic",
 });
 mocks.heicTo.mockResolvedValueOnce(
 new Blob([new Uint8Array(MAX_COMPRESSIBLE_SOURCE_BYTES + 1)], {
 type: "image/jpeg",
 }),
 );
 const { close } = stubCanvasPipeline(() => 200_000);

 const result = await prepareImageForAttachment(original, 1_000_000);

 expect(result.ok && result.file.name).toBe("large.jpg");
 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(result.ok && result.file.size).toBeLessThanOrEqual(1_000_000);
 expect(close).toHaveBeenCalled();
 });

 it.each([
 { label: "24 MP", width: 5712, height: 4284 },
 { label: "48 MP", width: 8064, height: 6048 },
 ])("accepts $label HEIC photos", async ({ width, height }) => {
 const original = makeHeicFile({ width, height });
 mocks.heicTo.mockResolvedValueOnce(new Blob(["jpeg"], { type: "image/jpeg" }));

 const result = await prepareImageForAttachment(original, 1024);

 expect(result.ok && result.file.type).toBe("image/jpeg");
 expect(mocks.heicTo).toHaveBeenCalledOnce();
 });

 it("rejects oversized HEIC dimensions before loading the decoder", async () => {
 const original = makeHeicFile({ width: 16_000, height: 4001 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "too-large",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("rejects invalid HEIC metadata before loading the decoder", async () => {
 const original = new File([new Uint8Array([1, 2, 3])], "broken.heic", {
 type: "image/heic",
 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "unreadable",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("reports unreadable when HEIC decoding fails", async () => {
 const original = makeHeicFile({
 name: "broken.heic",
 type: "image/heic",
 });
 mocks.heicTo.mockRejectedValueOnce(new Error("Invalid HEIC image"));

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "unreadable",
 });
 });

 it("rejects unsafe HEIC sources before loading the decoder", async () => {
 const original = new File(["photo"], "large.heic", { type: "image/heic" });
 Object.defineProperty(original, "size", { value: MAX_COMPRESSIBLE_SOURCE_BYTES + 1 });

 expect(await prepareImageForAttachment(original, 1024)).toEqual({
 ok: false,
 reason: "too-large",
 });
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });

 it("leaves supported images untouched without loading the HEIC decoder", async () => {
 const original = makeFile(1024);

 const result = await prepareImageForAttachment(original, 2048);

 expect(result.ok && result.file).toBe(original);
 expect(result.ok && result.recompressed).toBe(false);
 expect(mocks.heicTo).not.toHaveBeenCalled();
 });
});
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