+
+ // Seemingly at least Firefox prefers MP3 over Opus; tell it otherwise,
+ // and also preload the file since the user has selected audio.
+ var ding = document.getElementById('ding');
+ if (ding && ding.canPlayType && ding.canPlayType('audio/ogg; codecs="opus"') === 'probably') {
+ ding.src = 'ding.opus';
+ ding.load();
+ }