Here’s a part of a cabinet in my wardrobe where my printer lives. It’s a bit noisy with all those hard surfaces so I am just about to put up some foam padding on all 5 sides.
Is that stupidly dangerous?
You can see I have a smoke alarm there, but it won’t stop a fire on its own.
Edit: the cabinet has no door, it’s always open like in the photo, but the wardrobe door is generally closed. The room has some ventilation so smells do go away.
I would also recommend an anti-vibration mat (typically used for washing machines).