I’m not worried about a fire starting in the glowforge on long jobs (as I don’t do long jobs on cardboard, paper, fabric and the like). I’m worried about the arm the laser head is on becoming the slightest bit cockeyed, whether due to a software bug or a bit of something stuck over there in that side area or a minor motor malfunction. At that point the laser head pretty much stops moving, but the laser keeps burning. Now, unless the material under it is metal or stone, your chances of fire are much more realistic. Again, I’m only concerned if something unexpected happens.