v4: an audio file's waveform is made once by the server, and the player seeks on one accessible scrubber — every player downloaded the whole file a second time and decoded all of it in the browser to draw 150 bars, so a long FLAC cost tens of megabytes of memory per page, and the waveform could only be clicked: no drag, no keyboard, no slider for a screen reader. GET /api/dumps/:id/waveform now answers an audio dump's peaks, which lib/ffmpeg.ts decodes with ffmpeg on first request, mono at 8 kHz and streamed, keeps beside the thumbnails as the response itself, and serves with an ETag (a ten-minute MP3 takes about a second, then a few hundred bytes). The peaks are taken by shared/waveform.ts's peaksOf, scaled to the loudest so a quiet recording fills the track, and the dump form's preview of a file not yet uploaded decodes it with the same function, at 8 kHz in an OfflineAudioContext. Scrubber replaces Waveform and SeekBar: a role="slider" that seeks where a pointer lets go, follows a drag (the clock shows where it is held), takes arrows, Home and End, and draws the bars as one path with the played part clipped by a nested svg, so it moves smoothly and a timeupdate redraws two attributes instead of 150 rects; audio without a waveform, and video, get a plain bar. MediaPlayer reads whether it plays from the element's events alone, so a click no longer reports the change twice, its handles for PlayerProvider are stable callbacks instead of refs to refs, the drag no longer reattaches every listener, and the <source> children that src made dead are gone, with the mime prop. The file, thumbnail and waveform routes resolve their dump, token and caching through lib/dump-media.ts, and what is generated from an upload is named and removed in lib/ffmpeg.ts, the custom thumbnail by dump-service's customThumbnailPath, instead of paths spelled out in each. The test setup's play() and pause() fire their events as a browser does. 277 backend tests and 684 frontend tests pass, and deno check, tsc, eslint, doc:lint and i18n:compile --strict are clean; checked in the app with a real FLAC on its dump page and in the global player at 1280 and 390px, seeking by keyboard.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/test/setup.ts

@@ -150,10 +150,25 @@ class FakeAnimation extends EventTarget implements Animation {
 Element.prototype.animate ??= () => new FakeAnimation();
 Element.prototype.getAnimations ??= () => [];
 globalThis.scrollTo = () => {};
-HTMLMediaElement.prototype.play = function () {
+// jsdom plays nothing. These keep `paused` and fire `play` and `pause` as a
+// browser does, which the players' state follows.
+const playingMedia = new WeakSet<HTMLMediaElement>();
+Object.defineProperty(HTMLMediaElement.prototype, "paused", {
+  configurable: true,
+  get(this: HTMLMediaElement) {
+    return !playingMedia.has(this);
+  },
+});
+HTMLMediaElement.prototype.play = function (this: HTMLMediaElement) {
+  if (!playingMedia.has(this)) {
+    playingMedia.add(this);
+    this.dispatchEvent(new Event("play"));
+  }
   return Promise.resolve();
 };
-HTMLMediaElement.prototype.pause = function () {};
+HTMLMediaElement.prototype.pause = function (this: HTMLMediaElement) {
+  if (playingMedia.delete(this)) this.dispatchEvent(new Event("pause"));
+};
 HTMLMediaElement.prototype.load = function () {};
 // The emoji picker probes emoji support on a canvas; jsdom has none.
 Object.defineProperty(HTMLCanvasElement.prototype, "getContext", {