[Android Apps and Games] ACiDxCHRiST:
Really bad news, I am continuing to troubleshoot now, but my first indications are that there is a serious issue with Battery Charge Limit v1.1.1 on Android 8.1 with at least the Pixel 2 XL and maybe other devices.

I did a clean flash of my Pixel 2 XL yesterday to 8.1 with the factory image. The flashing process wiped the phone and ensured that all partitions are completely stock. I then flashed twrp(v3.1.1-beta2)+magisk(v14.5). I did not flash a custom kernel. I installed apps and finished setting up the phone to my liking including installing and configuring Battery Charge Limit to 80-78. I then went to bed and put the phone on the charger(non-rapid) with the battery at 20%. The lockscreen came on for a second as I plugged it in and I verified that the Battery Charge Limit notification popped up saying "charging to 80%".

When I woke up, I rolled over and unplugged my phone from the charger. The screen did not do its customary turning on when unplugging. I put my finger on the fingerprint reader and nothing happened. No unlock, no screen on, no haptic feedback. I then pressed the power button and again, no reaction. I then decided to hard reboot it by holding the power button. After 20 seconds of holding the power button, still no reaction. I plugged the phone back in to the charger and after a couple seconds a battery and charging plug icon popped up that I guess was trying to say that the battery was dead. After another couple of seconds the icon changed slightly but still was not the standard phone off charging animation. I held the power button for a couple of seconds and the phone booted.

With the phone still plugged in and now at the lockscreen, the battery showed 0%. I typed my PIN and unlocked it and verified that everything looked like it was working ok. I waited 60 seconds or so and the battery was still saying 0% so I hit the power button and decided to give it a minute or so of screen off charging before checking it again. A minute passed and I went to unlock the phone with the fingerprint reader and I felt the haptic feedback register the finger touch but the screen did not come on. I tried pushing the power button and the screen still did not come on. I pushed the power button a second time and the screen came on to the homescreen, unlocked. The battery was still at 0%.

I decided to see if the screen not coming on was repeatable. I pressed the power button and turned the screen off. When I went to turn the screen back on, the same exact thing happened, including the exact sequence needed to get the screen to come back on. At this point the battery had finally ticked up to 1%. So I left it screen off to charge a while. After the battery was at 25%, I unplugged it and played around with turning the screen off, and then back on a few times. Each time, it was the same experience as before, fingerprint reader would pulse haptic feedback after touching but the screen wouldn't come on, then it would take 2 presses of the power button with a 1 second delay between to get the screen on.

I tried rebooting the phone multiple times and the issue remained. There was one additional consideration after a reboot. If I did not unlock the phone after a reboot before the screen timed out and turned off, I would not be able to get the screen to come on at all. I could put my finger on the sensor, it would vibrate, I would lift my finger and immediately put it back on the scanner, and it would vibrate again. I could do this endlessly. No amount of pressing the power button or touching the fingerprint scanner would make the screen turn on. Also, if I long pressed the power button, I got the haptic feedback like you get when you long press the power button to get the reboot menu. If I did enter my PIN and unlock before the screen timed out after the reboot, then I experienced the earlier behavior I spoke of.

I decided to Clear Data on Battery Charge Limit and uninstall it. I did that and everything is now working fine. It is possible that it was just a coincidence and I have more testing to do to try to replicate the issue and isolate the specific cause. I just wanted to get this detailed report out here so that if anyone else is experiencing anything similar, they can chime in.

...more to come.