I faced the same issue with Lineage 18 (Android 11) on a Galaxy A5 (2017). It’s due to Android 10+ privacy limitations that disable camera access for apps running in background/with screen off.
However, you can add an official plugin called “Fade at start” that basically show a black screen instead of turning it off. If you’re running an OLED screen, no big deal, power consumption should remain the same while avoiding burn-in. 
Tasker automation that kills the process and starts it again based on a schedule?
Does anyone figure out how to turn on android phones after power outage automatically?
if it doesn’t turn on by itself all this app is for demo purpose.
I think by now someone must figure out this problem.
this app is to repurpose old android phones with old battery won’t last for any meaningful time, any glitch on power it turn off.
Hmm… Maybe it is a setting somewhere on your phone? My phone would turn on automatically if/when it gets the power. Can’t recall I did anything special in that regard.
And then, after the phone is on, with this setting, IP Webcam Pro would start the video feed automatically with this setting:
= = =
The setup above has been serving me well for the last 6 years - yes I’m still using the same old android phone. It’s a rooted Sony, and I rooted specifically so that I can set battery charge limit to 70% - the battery is still alive and kicking to this day.
