You hit the Bat-Getaway mode and tripped the Bat-Smoke-Screen. Congrats on the clean getaway....you mastered the mode.

Annnd, maybe it wasn't so much heat as it was melted plastic. My guess....pinched wire and some toasted insulation. A little wire can generate a lot of smoke. Ask me how I know..................

And a good chunk of those may not have been avoided by turning of the power when leaving. The vast majority of structure fires are caused by humans such as leaving a candle unattended, burning food on the stove, arson, construction, etc. Lightning causes a bunch as well.

I was a fire chief - medic - and law enforcement officer for over 25 years. I worked a lot of structure fires in those years , and I can say it was a rarity to have an un-modified appliance fail which caused a fire, but it does happen. For the record, I turn my games off and unplug them when they are not in use in my home, but I do that because of the Mid-west storms. I am way more worried about lightning or power surges taking out my games than I am about the house busting into flames....lol But as they say, an ounce of protection is worth a pound of cure, so I would never fault someone for being too careful.