Re: You don't say
"Dare to fall asleep while watching youtube and you will be certain to wake up to a watch history full of utter crap."
Turn off auto play is my advice. A friend swears if he falls asleep while watching anything on YouTube he always wakes up to find it playing a Mr Carlson's Lab video*. Not something I'd consider a problem as I love those videos, but said friend finds the eponymous Mr Carlson creepy for some reason.
* Incredibly in depth videos on restoring electronic test equipment.