sleepTimer: stopped working after latest client update

[0ln]

The sleep timer completely stopped showing up after a client update.

Spotify for Windows (64 bit)
1.2.58.498.g6afe77b7
Spicetify v2.39.5
Theme: Default Dynamic / Base
Extensions: webnowplaying.js, shuffle+.js, hidePodcasts.js, quickQueue.js, playNextWrapper.js, playlistIntersection.js, showQueueDuration.js, fullAlbumDate.js, oldCoverClick.js, sleepTimer.js, Vibrant.min.js, default-dynamic.js
Custom apps: marketplace, eternal-jukebox

I have had the same issue on Spotify for Linux.
The extension was installed through the marketplace. It is the only one that stopped working.

[EJSnow]

I'm also having this issue, the sleep timer doesn't work on Spotify 1.2.60 on Arch Linux. If I had to guess, it's Spotify's recent-ish messing with the UI (making what was the navbar just for your library, and moving navigation to the top bar) that broke it.