Revert "perf(fs-player): cut CPU under WebKitGTK software compositing"

This reverts commit 77edfaa867.

Restores the full Apple Music-style lyrics visuals from PR #205 on Linux:
rAF spring scroller, per-line scale transforms, text-shadows, title glow,
album-art/play-button outer glows, mesh-blob radial gradients, and the
FS-art opacity crossfade. PR #205's author noticed the Linux codepath
lost the intended feel — the CPU tradeoff is accepted.

The trigger-ref fix from 25537f27 for the lyrics menu stays in place.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/components/FullscreenPlayer.tsx

@@ -434,40 +434,20 @@ const FsSeekbar = memo(function FsSeekbar({ duration }: { duration: number }) {
   const inputRef    = useRef<HTMLInputElement>(null);
 
   useEffect(() => {
-    // Cache the last applied values so we can skip DOM writes when nothing
+    const s = usePlayerStore.getState();
-    // changed. The store subscription fires on every state change (queue,
+    const pct = s.progress * 100;
-    // volume, currentTrack…), not just progress, so without this guard we
+    if (timeRef.current)   timeRef.current.textContent  = formatTime(s.currentTime);
-    // were writing identical width/textContent strings dozens of times per
+    if (playedRef.current) playedRef.current.style.width = `${pct}%`;
-    // second — each one triggers a style invalidation in WebKitGTK.
+    if (bufRef.current)    bufRef.current.style.width    = `${Math.max(pct, s.buffered * 100)}%`;
-    let lastTime  = -1;
+    if (inputRef.current)  inputRef.current.value        = String(s.progress);
-    let lastPct   = -1;
-    let lastBufW  = -1;
-    let lastProg  = -1;
 
-    const apply = (s: ReturnType<typeof usePlayerStore.getState>) => {
+    return usePlayerStore.subscribe(state => {
-      const pct  = s.progress * 100;
+      const p = state.progress * 100;
-      const bufW = Math.max(pct, s.buffered * 100);
+      if (timeRef.current)   timeRef.current.textContent  = formatTime(state.currentTime);
-      const sec  = s.currentTime | 0;
+      if (playedRef.current) playedRef.current.style.width = `${p}%`;
-      if (sec !== lastTime) {
+      if (bufRef.current)    bufRef.current.style.width    = `${Math.max(p, state.buffered * 100)}%`;
-        lastTime = sec;
+      if (inputRef.current)  inputRef.current.value        = String(state.progress);
-        if (timeRef.current) timeRef.current.textContent = formatTime(s.currentTime);
+    });
-      }
-      if (pct !== lastPct) {
-        lastPct = pct;
-        if (playedRef.current) playedRef.current.style.width = `${pct}%`;
-      }
-      if (bufW !== lastBufW) {
-        lastBufW = bufW;
-        if (bufRef.current) bufRef.current.style.width = `${bufW}%`;
-      }
-      if (s.progress !== lastProg) {
-        lastProg = s.progress;
-        if (inputRef.current) inputRef.current.value = String(s.progress);
-      }
-    };
-
-    apply(usePlayerStore.getState());
-    return usePlayerStore.subscribe(apply);
   }, []);
 
   const handleSeek = useCallback(

src/styles/components.css

@@ -3854,22 +3854,6 @@
 html.no-compositing .fsr-lyrics-overlay { -webkit-mask-image: none; mask-image: none; }
 html.no-compositing .fsr-lyrics-rail    { will-change: auto; }
 
-/* Apple-style FS lyrics — strip GPU-only effects.
-   Without compositing, transform: scale() on every line forces a per-line
-   software repaint on each active-line change, and the 48 px / 32 px blur
-   text-shadows repaint on every word tick. Replace with opacity + colour,
-   which are cheap text-only repaints. */
-html.no-compositing .fsa-lyric-line {
-  transform: none;
-  transition: color 380ms cubic-bezier(0.25, 0.46, 0.45, 0.94),
-              opacity 380ms cubic-bezier(0.25, 0.46, 0.45, 0.94);
-}
-html.no-compositing .fsa-lyric-line.fsal-past   { transform: none; }
-html.no-compositing .fsa-lyric-line.fsal-active { transform: none; text-shadow: none; }
-html.no-compositing .fsa-lyric-line.fsal-active .fsa-lyric-word.active {
-  text-shadow: none;
-}
-
 /* ── no-compositing overrides ─────────────────────────────────────────────────
    Applied only when WEBKIT_DISABLE_COMPOSITING_MODE=1 is set (Arch Linux etc).
    Replaces GPU-only effects (backdrop-filter, CSS filter, mask-image) with
@@ -3894,19 +3878,10 @@ html.no-compositing .fs-portrait {
 }
 
 /* Portrait wrap: replace mask-image fade with a pseudo-element overlay gradient.
-   pointer-events: none on wrap means the overlay never blocks clicks.
+   pointer-events: none on wrap means the overlay never blocks clicks. */
-   Also drop translateZ(0) — useless GPU layer hint without a compositor. */
 html.no-compositing .fs-portrait-wrap {
   -webkit-mask-image: none;
   mask-image: none;
-  transform: none;
-}
-
-/* FS art crossfade: opacity transition compositing is GPU-cheap, software-expensive.
-   Snap instantly between covers; visually a hard cut, but the previous layer is
-   replaced before the user can really notice. */
-html.no-compositing .fs-art {
-  transition: none;
 }
 html.no-compositing .fs-portrait-wrap::before {
   content: '';
@@ -3924,16 +3899,12 @@ html.no-compositing .fs-portrait-wrap::before {
 
 /* Lyrics fade overlays: gradient-only, no backdrop-filter — fine in no-compositing */
 
-/* Mesh blobs: stop animations + flatten to a solid dark fill.
+/* Mesh blobs: stop animations — in software mode each frame composites surfaces
-   Even static, the 130 × 130 % radial-gradient with color-mix() is recomputed
+   larger than the screen (blob-a is 130 × 130 % of the viewport); on high-DPI
-   on every paint, and the `transition: background 400ms` on accent change
+   displays this saturates the CPU and drops the player to ~10 FPS.
-   re-rasterises the giant surface for nearly half a second per track switch.
+   Static gradients are preserved; only the slow pan animation is removed. */
-   Atmosphere is sacrificed; the dynamic accent is preserved on title /
-   seekbar / controls via their own var(--dynamic-fs-accent) bindings. */
 html.no-compositing .fs-mesh-blob {
   animation: none;
-  background: #06060e;
-  transition: none;
 }
 
 /* Seekbar played bar: remove box-shadow — its width changes on every playback
@@ -3942,45 +3913,6 @@ html.no-compositing .fs-seekbar-played {
   box-shadow: none;
 }
 
-/* Track title: drop the 40 px text-shadow glow — paints a giant blur on a
-   clamp(28–68 px) font and re-rasterises whenever anything around it
-   redraws (cluster updates, seekbar tick, dynamic accent change). */
-html.no-compositing .fs-track-title {
-  text-shadow: 0 2px 6px rgba(0, 0, 0, 0.65);
-  transition: color 200ms ease-in-out;
-}
-
-/* Album art wrap: replace the accent-coloured outer glow with a flat
-   shadow. The 28 px blur was repainting every accent change. */
-html.no-compositing .fs-art-wrap {
-  box-shadow: 0 6px 18px rgba(0, 0, 0, 0.7), 0 0 0 1px rgba(255, 255, 255, 0.07);
-  transition: none;
-}
-
-/* Play button: drop accent glow + hover filter. Keep flat dark shadow only. */
-html.no-compositing .fs-btn-play {
-  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.55);
-}
-html.no-compositing .fs-btn-play:hover {
-  filter: none;
-  box-shadow: 0 6px 18px rgba(0, 0, 0, 0.65);
-}
-
-/* Rail-style FS lyrics: same problems as Apple style — 28 px text-shadow
-   blur on every active line + every active word, plus per-line transform
-   scaleX. Strip them; rail still scrolls fine via the parent translateY. */
-html.no-compositing .fsr-lyric-line {
-  transition: color 280ms ease;
-  transform: none;
-}
-html.no-compositing .fsr-lyric-line.fsrl-active {
-  text-shadow: none;
-  transform: none;
-}
-html.no-compositing .fsr-lyric-line.fsrl-active .fsr-lyric-word.active {
-  text-shadow: none;
-}
-
 /* Chat */
 .chat-popup {
   position: absolute;

src/utils/springScroll.ts

@@ -40,15 +40,6 @@ export class SpringScroller {
 
   scrollTo(targetY: number) {
     this.target = Math.max(0, targetY);
-    // Software-rendered Linux: replace our 60 fps rAF spring with the
-    // browser's native smooth scroll. The browser handles easing internally
-    // (one animation, not 60 JS callbacks per second) and we still get a
-    // smooth visual instead of a hard snap.
-    if (document.documentElement.classList.contains('no-compositing')) {
-      this.stop();
-      this.container.scrollTo({ top: this.target, behavior: 'smooth' });
-      return;
-    }
     if (this.rafId === null) this.tick();
   }