const setPlaybackRate = (video) => { const speed = parseFloat(settings.defaultVideoSpeed); video.playbackRate = speed; SpinQuery.condition(() => video, () => video.playbackRate !== speed, () => video.playbackRate = speed); }; Observer.videoChange(() => { const video = dq('.bilibili-player-video video'); if (!video) { return; } setPlaybackRate(video); });