library-development.spec.js starts the actual JS dev CLI and typed runner on an atomically assigned fixture port. It checks generated TS/Less/SVG/inline-worker assets, automatic reload on edits and recovery after a compiler error in all three engines. It owns and stops only its child server, never the user's port 8082 session. SIGTERM must settle the child naturally with exit0. Its second case serves actual docs/Monaco, executes TypeScript and plays/pauses/seeks a local MP4, checking a decoded canvas frame. The attachment records browser/version, OS and actual core/media hashes; the tracked core5.4.1 asset is not a new release candidate. Analytics/ads are inert routes; real-device and remote OS checks remain separate.

site-loading.spec.js covers actual desktop/mobile loading, dependency order, failure/retry/AMD restoration, example priority, repeated Run and stale responses, plus Run Code and language routing. External analytics/ads are inert test routes; no advertising service or native device acceptance is implied. Keep this browser run serial with heavy compiler baselines after observing local setup contention.

editor-declarations.spec.js loads the repository Monaco with the 22 declarations actually listed in common.js, checks positive/negative consumers and runs emitted Chapter code through ready/destroy with controlled media. VAST coverage is types only, not advertising SDK execution. The unreferenced legacy WebSR declaration asset is preserved; this test follows the actual editor's library list.

docs-smoke.spec.js verifies the documentation runner in three engines with actual core/media, controlled failures and three selected generated snippets. It checks pending readiness beyond the former 100ms timer, returned/unhandled rejections, ready/destroy errors, missing scripts, deadlines, frame/global/timer cleanup and storage restoration. It does not execute all 233 documentation cases or prove remote SDKs/features. DPIP-MEDIA-01's exact WebKit intrinsic/layout size pairs remain explicit observations; this suite does not close that risk.

yarn test:browser test/browser/ads.spec.js tests actual Ads 1.0.6 and candidate code with published 4.5.5/5.4.1 and candidate cores using local image/video media. It covers actual decoded pixels, countdown, skipping, content restoration, 404 and source replacement. Published-only rejection cases inject an exact play failure; they do not certify device autoplay policies. See Ads validation. Candidate lifecycle cases check early/duplicate skip, real media release after destroy and observed internal play rejections. The server exposes the verified 4.5.5 bundle separately and records its fingerprint; the fixture uses the shared template.$video surface.

Audio Track tests use the source and frozen 1.1.0 plugin on both cores. The local AAC fixture has a pinned hash and generation command in media/audio-tone.json and uses the existing Range server. The suite retains published cleanup/native-pause defects as explicit observations. See audio validation for passed scope and device limitations.

Use the pinned Node and Yarn versions, then run:

yarn install --frozen-lockfile
yarn test:browser:install
yarn test:browser
yarn test:browser --project=chromium
yarn test:browser:report

The three projects run actual Chromium, Firefox and WebKit. They use isolated browser contexts, no retries, a loopback server on 8084, and no existing dev server. Set ARTPLAYER_BROWSER_PORT to use another free port. The server builds core and chapter from current JS/TS entries in memory; it does not modify dist or docs outputs. Restart the test command after source changes.

hls-control.spec.js separately builds HLS control and verifies a pinned Hls.js 1.5.17 archive. Its local playlists/segments are generated fixtures with checked hashes. Windows WebKit lacks MSE: one explicit capability/error-cleanup test covers that limitation and its 14 playback cases are skipped with a reason. Chromium/Firefox run the full four-combination HLS matrix. This is not Safari playback approval; see HLS validation for evidence and open gates.

playback.spec.js tests published/current core with current chapter, real decoded frame colors, media time advancing, pause, seek, source change to the existing docs video, destroy and real HTTP failure. These are initial smoke contracts, not full chapter or lifecycle coverage. fixtures.js captures browser version, actual scripts/media hashes, page errors, console errors, failed requests and final state. Tests attach decoded pixels and server-side media requests too. Windows WebKit media requests are not reliably visible to Playwright's page network events; use the loopback request log to prove that media was fetched. Its videoWidth can reflect layout size, so intrinsic-size compatibility is a separate test, not the playback-success predicate. Chromium's net::ERR_ABORTED and Firefox's NS_ERROR_PARSED_DATA_CACHED may cancel media range requests after buffering. The successful-playback tests allow only the exact engine-specific code, same-origin media type and two URLs bearing the current test ID; raw failures remain in reports. See Mozilla's media-cache explanation.

Reports, failure screenshots and traces are under refactor/.cache/browser/. They contain local test URLs and paths. JSON and HTML are regenerated each run; archive them before another run if evidence must be retained. A successful HTTP page fetch does not validate its editor UI.

Files and routes

server.mjs: current/published artifact provenance, docs serving, Range and controlled failures.
player.html: lightweight page, real ArtPlayer constructor and user-gesture play/pause buttons.
fixtures.js: per-test error and provenance attachment; contexts/storage are Playwright-owned.
playback.spec.js: behavior assertions shared by browser and core version.
media/: committed synthetic fixtures. CI needs no FFmpeg to use them.

/test/manifest.json identifies every mapped core/chapter artifact and synthetic media file by SHA-256. /published/<package>.js verifies the frozen npm archive/member from BASE-01. /candidate/<package>.js maps the current build. Existing docs /compiled/<package>.js and /uncompiled/<package>/index.js are aliases for that candidate. Other compiled/uncompiled paths fail explicitly; add a verified mapping before testing another package, rather than serving stale build output. Other docs pages, examples and samples use their existing paths without source edits.

/test/pattern.mp4 and .webm support GET/HEAD and single byte ranges (including suffix ranges). Invalid ranges return 416. /test/fail.mp4 always returns 503. Add a unique ?case=<test-id> to media URLs and inspect /test/requests.json?case=<test-id> for actual server requests. The log is bounded and server-local; it is not a production endpoint or a substitute for decoded frames.

To test extracted candidate UMD files, set ARTPLAYER_BROWSER_ARTIFACTS to a JSON file:

{
  "artplayer": "./extracted/artplayer/dist/artplayer.js",
  "artplayer-plugin-chapter": "./extracted/chapter/dist/artplayer-plugin-chapter.js"
}

Paths resolve relative to that JSON. Both keys are required; missing files abort startup. No source fallback is allowed in this mode. ENG-07 owns tarball creation and broader consumer checks. For manual docs interaction, run node test/browser/server.mjs and open the existing editor URL on 8084 with chapter's libs/example parameters. EX-03 still owns the full Monaco Run/TS/storage workflow, all examples and external SDKs. The lightweight page does not complete that task.

Synthetic media provenance

Generated locally from FFmpeg's testsrc2, without external footage or audio, using ffmpeg version 2025-11-12-git-6cdd2cbe32-full_build-www.gyan.dev:

ffmpeg -f lavfi -i testsrc2=size=320x180:rate=24 -t 8 -an -c:v libx264 -profile:v baseline -pix_fmt yuv420p -movflags +faststart test/browser/media/pattern.mp4
ffmpeg -f lavfi -i testsrc2=size=320x180:rate=24 -t 8 -an -c:v libvpx -b:v 160k test/browser/media/pattern.webm

MP4 SHA-256: 0ad1d7ad286aec6e0fa9e27fc1e487e7277df2e603e30040fb942365763d0233. WebM SHA-256: 9d3c2b3dec9581a599de2d6732992ef7846790e0d1368e6e131bd339b39e984f. MP4 is the initial playback contract; WebM is available for subsequent codec-specific cases. Do not regenerate fixtures silently: update hashes and decoded-frame checks together.

The docs assets/sample/video.mp4 remains an existing sample with its original provenance limits tracked by BASE-MEDIA-01. The new synthetic fixtures do not resolve rights for existing media. Browser binaries/codec support vary by OS; these projects do not replace Safari/iOS/Android device checks. See the official browser guidance.

Withheld media diagnostics

test/helpers/media-gate.js binds a temporary HTTP server to loopback and withholds the tail of the pinned media until the test calls release(). Its default response keeps the full Content-Length and streams the prefix; the diagnostic completeRanges mode sends a bounded 206 response and holds the later range. Both preserve exact bytes and a strong ETag. Partial range semantics follow RFC 9110 section 15.3.7. node --test test/media-gate.test.js verifies actual HTTP bytes, headers and release.

audio-buffering.spec.js requires trusted waiting after actual clock progression, then release, resumed clocks and synchronization across old/new core/plugin pairs. It currently has unresolved Windows WebKit failures; do not skip them or count the native diagnostic below as equivalent acceptance. See refactor/audio-validation.md.

media-gate-native.spec.js removes all ArtPlayer instances and uses a native element with preload=auto. It records whether playback and starvation were observed for both response modes. A passing diagnostic only proves observation plus successful playback after release; inspect its progressed/waiting flags before claiming buffering. These capability observation timeouts do not relax the integration assertions. Archive the report and results (including traces) before starting another browser suite.

Danmuku input, scheduler, resources and heatmap-density specs accept ARTPLAYER_DANMUKU_ARTIFACT for a built main/legacy file; unset it to compile the current JS/TS entry. Run each format sequentially and wait for the command's final exit before copying reports or launching the next format. A visible last test line does not prove reporter/trace teardown is finished. These runs share the server port and output directory, so simultaneous invocations can corrupt failure evidence. For a timeout, inspect the retained trace before changing the test or implementation; browser startup and pre-plugin playback delays are different from plugin execution. The density regression retains 16000 rows, real playback and SVG/pixel geometry at two widths. A diagnostic pass does not waive the full matrix or long-load acceptance.

danmuku-timing-diagnostic.spec.js records independent native RAF/media progress and the original eligibility getter under an 800ms CPU block or 600ms asynchronous visibility callback. Its async case asserts that the candidate retains all three rows and serial callbacks; the fixed published baseline retains its missing middle row. CPU-block observations remain diagnostic, not no-loss acceptance. Both it and danmuku-lifetime.spec.js accept the same artifact override. The latter verifies the full visible lifetime after a controlled delay to an actual Worker request.

danmuku-stability.spec.js runs three native 14-second media cycles at 2 or 20 rows per second, appending through the public load(rows) contract. The candidate must deliver and recycle every row once, preserve state membership and reuse actual node identities. Its 90-second per-case deadline budgets the 42 seconds of media plus setup/teardown; it is not a relaxation of other tests. Heap readings remain observations. No media/RAF clock is replaced or ready state seeded here. danmuku-mask-boundary.spec.js verifies the core-owned root and external CSS mask across commands and destroy(false), with actual video and placement Worker. It uses explicit ready rows for resource setup and a fixed SVG mask; it does not load the Mask SDK/model or provide timestamp-delivery evidence.

danmuku-mask-native.spec.js loads the actual built Mask/SDK and fixed local MediaPipe assets with native video. It verifies bitmap alpha, stop/restart/destroy, then actual Danmuku delivery after model readiness, pause, seek and CSS web fullscreen with candidate, published and actual 5.3.1-beta.1 cores. Set ARTPLAYER_MASK_ARTIFACT to a main/legacy global artifact; ESM is not supported by that override. Run formats sequentially and archive each completed report. The startup time=6 row remains diagnostic because initial model work can coincide with a missed narrow timestamp window. A passing post-ready combination is not proof of startup losslessness, private GPU/WASM closure, OS fullscreen or devices. See refactor/changes/2026-09-14-PKG-MASK-05-native-checkpoint.md for exact limits.

jassub-native.spec.js runs actual published JASSUB 1.1.0, its native Worker, fixed local WASM/font and authored ASS cues with offscreenRender=false. It checks real canvas pixels before/after seek, CSS web fullscreen and normal destruction. Windows WebKit currently fails the default frame-clock path; the explicitly selected ARTPLAYER_JASSUB_ON_DEMAND=false diagnostic passes on the candidate core. This is a retained historical failure, not a waived browser gate. The server must serve WASM as application/wasm for native streaming compilation. Archive failed and successful runs independently. See the PKG-JASSUB-02 change record.

For candidate registration regressions, set ARTPLAYER_JASSUB_ARTIFACT to a built main/legacy global file. Those runs also destroy the exposed instance before host cleanup. ARTPLAYER_JASSUB_CUSTOM_CANVAS=true supplies a caller-owned canvas and asserts it remains connected after destroy(false). The native report records the artifact hash and both mode choices. This does not change the default published baseline or establish ESM/offscreen/device acceptance.

JASSUB Firefox diagnostics retain the canonical failing cases. Set ARTPLAYER_JASSUB_OFFSCREEN=default to exercise native capability selection. ARTPLAYER_JASSUB_ASYNC_RENDER=false explicitly selects synchronous rendering; ARTPLAYER_JASSUB_READBACK_FRAME=true waits one animation frame before readback. Neither diagnostic changes the default candidate or constitutes a runtime fix. playwright.jassub-diagnostic.config.js requests Firefox software WebRender for comparison only; it is not the canonical browser acceptance configuration.

jassub-platform.spec.js isolates native video and a minimal canvas Worker under candidate/published cores and a script-free native host. All hosts resize to the viewport. Default drawing uses fillRect; ARTPLAYER_JASSUB_CONTROL_BITMAP=true selects actual createImageBitmap/drawImage/close and records worker stage times. ARTPLAYER_JASSUB_CONTROL_IDLE_READBACK=true pauses submissions while waiting for all draw acknowledgements before copying the display canvas. This is a deliberate scheduling diagnostic, not unchanged production timing. Hosts without canvas transfer use main-thread fillRect and do not verify the Worker/ImageBitmap path. The report records these distinctions and never infers a JASSUB fix from a control pass. Preserve each raw report/results directory before the next browser command. See the isolation record.

ARTPLAYER_JASSUB_SCREENSHOT=true adds a separate observation path to the native JASSUB spec. jassub-display.js decodes a clipped composited page PNG using the pinned root-only pngjs development dependency; it never copies the transferred canvas. This mode uses green ASS glyphs, distinct 0-30s and 40-110s cue windows, and seeks to 50s. It checks the initial cue time, visible pixels, changed glyph signature, playback advance, fullscreen geometry and a hidden/restored negative control. Normal readback fixtures and timeouts stay unchanged. Reported subtitle hashes identify the actual selected ASS, not the white baseline. Screenshots are attached at named phases; errors from individual polling attempts are retained. The fixture's automatic failure screenshot runs after cleanup and may show an empty player; use the named pre-cleanup screenshots for visual claims.

Chapter quality combinations attach chapter-restart-observations: completed read calls include host wall time/elapsed time and browser monotonic time/origin. Public/native chapter events also carry browser timestamps. Preserve those clocks when diagnosing a timeout: the historical failure includes a single ~10-second evaluate returning an already-recorded restart, not seven seconds of fast empty reads. These observations do not expand the timeout or waive the open timing and physical-device acceptance in PKG-CHAPTER-05.

VTT combination tests verify actual preview screenshot pixels, Chapter coexistence, native/web fullscreen, source switching and cleanup across five recorded core inputs. The 5.1.6 server route verifies its frozen npm archive/member fingerprints. Historical 1.0.1 has a distinct valid 5.1.6 pair and explicit later-core name-conflict tests; expected historical failures are not compatibility passes. Later 1.0.x compiled bundles receive their documented compact-arrow fixture, while ordinary syntax failures remain in the historical parser tests. Mobile cases use an Android UA and synthetic DOM touches through the real core handlers, not trusted hardware input. Fullscreen mouse placement first waits for the progress control to be stable; the earlier hidden-preview screenshot timeout remains in the checkpoint evidence.