fix webkit video conversion bug

src/misc.ts

@@ -676,6 +676,28 @@ export const isSafari = () => {
 	return result;
 };
 
+let isWebKitCache: boolean | null = null;
+export const isWebKit = () => {
+	if (isWebKitCache !== null) return isWebKitCache;
+	if (typeof navigator === 'undefined') return (isWebKitCache = false);
+
+	const ua = navigator.userAgent || '';
+	const maxTouchPoints = navigator.maxTouchPoints || 0;
+
+	// iOS/iPadOS detection:
+	// - All iOS/iPadOS browsers use WebKit (WKWebView)
+	// - iPadOS 13+ can report "Macintosh" in UA; detect via touch points
+	const isIOSLike
+    = /iPhone|iPad|iPod/i.test(ua) || (/Macintosh/i.test(ua) && maxTouchPoints > 1);
+
+	// On iOS/iPadOS: always WebKit (even if UA says CriOS/Edg/OPR/etc.)
+	if (isIOSLike) return (isWebKitCache = true);
+
+	// Off iOS: only Safari is WebKit on mainstream desktops
+	const result = isSafari();
+	return (isWebKitCache = result);
+};
+
 let isFirefoxCache: boolean | null = null;
 export const isFirefox = () => {
 	if (isFirefoxCache !== null) {

src/source.ts

@@ -12,6 +12,7 @@ import {
 	binarySearchLessOrEqual,
 	closedIntervalsOverlap,
 	isNumber,
+	isWebKit,
 	MaybePromise,
 	mergeRequestInit,
 	promiseWithResolvers,
@@ -209,7 +210,13 @@ export class BlobSource extends Source {
 	private async _runWorker(worker: ReadWorker) {
 		let reader = this._readers.get(worker);
 		if (reader === undefined) {
-			if ('stream' in this._blob) {
+			// WebKit has critical bugs with blob.stream():
+			// - WebKitBlobResource error 1 when streaming large files
+			// - Memory buildup and reload loops on iOS (network process crashes)
+			// - ReadableStream stalls under backpressure (especially video)
+			// Affects Safari and all iOS browsers (Chrome, Firefox, etc.).
+			// Use arrayBuffer() fallback for WebKit browsers.
+			if ('stream' in this._blob && !isWebKit()) {
 				// Get a reader of the blob starting at the required offset, and then keep it around
 				const slice = this._blob.slice(worker.currentPos);
 				reader = slice.stream().getReader();