This is less useful than it sounds because there’s no integrated night vision, unlike even the cheapest ip cams. So really only works as a webcam.
Note that I have no specific knowledge on the subject ; it's quite possibly a fear without any reasonable ground.
But I had a cheap speaker that I used with a Chromecast audio to listening to podcasts ; I left it always on and... I came back just in time one night, the speaker was producing a large dark smoke.
I almost put fire to one of the oldest habitation building in Paris (1704) - with a lot of apparent wood etc. :-(
Not proud of it, but good lesson. I recently read about the risk of fire in cheap replacement phone chargers. Google's ought to be of quality but... still a no-no for me.
Obviously, advice from people with knowledge on the issue will be appreciated.
Having it plugged in, OTOH, probably doesn’t matter. There’s safety IC to prevent overcharging. Actually fully draining, mechanical damage, water damage etc. are more dangerous, which can happen during normal use anyway.