The battery on my new Lenovo M11 tablet was draining fast and it didn't make any sense because the tablet and battery is brand new. It's supposed to last all day. Turns out it was the Facebook app running in the background nonstop spying on everything I'm doing on the tablet and using all the battery power. Deleted the app. Problem is fixed.
I've seen Chrome, Edge, and Teams do that in Windows, too. It used to be an indicator of a poorly made application. Now it's an excellent indicator of spying.
Addendum:
BTW, if anyone wants to know, I recommend using a locked down Firefox, or possibly even better, LibreWolf (which comes already locked down).