I could reproduce it on a xa2 with 4.4.0.64:
- have quite full memory (dont know if necessary)
- open camera app, camera works
- close camera app
- open plantnet (android app) and start the camera from there
- IS camera error popup, SHOULD camera works
- wait, close apps (actually closed plantnet only i think)
- start plantnet, open camera in there
- camera works
- close plantnet
- open camera app
- IS camera black, SHOULD camera works
everything in normal quick succession except the waiting part