you can see unsoldered headphone or amp connectors in the background. Normal people don’t keep those just lying around. So I don’t think the soldering comment is too far off mark.

Also the whole post doesn’t make sense. OP barely responds to anyone. In the stuff he does respond with it makes even less sense. And yeah you can see the melted plastic in the picture so it’s pretty clear where the mouse was sitting when it melted. I’m guessing OP removed the mouse and then torched even more of the desk to make it look believable, but forgot about the bottom of the mouse.