I'm not going to lie...this is based on a true story. A quick explanation about the end of this video: I did it for "Shave For A Cure" (for the Leukemia and Blood Foundation)
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