Trackmark by hellblazeerr

Trackmark is a browser extension that scrobbles what you listen to on YouTube Music, SoundCloud and Apple Music to your Last.fm profile. It shows your current track as Now Playing and scrobbles it once you’ve listened to half the track or four minutes, whichever comes first, following Last.fm’s scrobbling rules. Scrobbles are queued if you’re offline and sent when you reconnect. It only runs on supported music sites, and you can switch it off globally or per site at any time. It never runs on regular YouTube videos. Your Last.fm session is stored locally in your browser, and no data is sent anywhere except to Last.fm.