A few people wanted some longer finger fluttering so here ya go hahah btw finger fluttering for a long time is a lot harder than you think. Go ahead and try it. ..See? Woah. Okay bye.
To listen while using other apps, switch the player to Picture-in-Picture (PiP) during playback — it keeps playing in a small floating window (the screen stays on).
To listen with the screen fully off, in-browser playback stops by YouTube's design. Open the video in the YouTube app to keep listening where background playback is supported (e.g. with YouTube Premium).
Open in YouTube app