You should've seen how many weird looks I got lol The things I do for you guys lol BTW keep in mind that there will be noise, music, people talking because it is obviously at the store Please feel free to leave suggestions! :)
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