diff --git a/web/static/app.js b/web/static/app.js
index 33d6ccf..1d6e0ec 100644
--- a/web/static/app.js
+++ b/web/static/app.js
@@ -560,33 +560,34 @@ function scrollToCurrentTrack() {
 
 // ── Boot ──────────────────────────────────────────────────────────────────────
 
+// Replace text and tune font so the symbol fills ~¾ of the button.
+// Centering is already handled by flex on .btn.
+// Defined outside if-block — function declarations inside blocks are
+// forbidden in strict mode on older engines and can kill the whole script.
+function legacySym(id, text, size) {
+  var el = $(id);
+  el.textContent     = text;
+  el.style.fontSize  = size;
+  el.style.fontWeight = 'bold';
+  el.style.letterSpacing = '2px';
+}
+
 // Replace emoji with legacy symbols on iOS 9 where the glyphs are missing.
-// Centering is already handled by flex on .btn — we only set size/weight here.
 if (isLegacyIOS) {
-  // Helper: replace text and tune font so the symbol fills ~¾ of the button.
-  function legacySym(id, text, size, weight) {
-    var el = $(id);
-    el.textContent = text;
-    el.style.fontSize   = size;
-    el.style.fontWeight = weight || 'bold';
-    el.style.letterSpacing = '2px';
-  }
-
   // Transport controls (btn-h = 64px):
-  //   two-char symbols (<<, >>) → 26px bold; single-char (■) → 36px bold.
-  //   ▶ is natively supported on iOS 9 and already 32px via .btn-play.
-  legacySym('btn-prev', SYM.prev, '26px');   // <<
-  legacySym('btn-play', SYM.play, '36px');   // ▶
-  legacySym('btn-stop', SYM.stop, '36px');   // ■
-  legacySym('btn-next', SYM.next, '26px');   // >>
-
-  // Volume mute (48px tall): short text, large and bold
+  //   two-char symbols (<<, >>) → 26px bold; single-char (■ ▶) → 36px bold.
+  legacySym('btn-prev', SYM.prev, '26px');
+  legacySym('btn-play', SYM.play, '36px');
+  legacySym('btn-stop', SYM.stop, '36px');
+  legacySym('btn-next', SYM.next, '26px');
+
+  // Volume mute (48px tall)
   legacySym('btn-mute', SYM.volOn, '16px');
 
   // Playlist action button (52px tall)
   legacySym('btn-show-playlist', SYM.playlist, '18px');
 
-  // Kill button: just drop the emoji, keep the label text
+  // Kill button: drop the emoji, keep the label
   $('btn-kill').textContent = SYM.skip + ' Überspringen';
 }