We, the users of this forum whom have been around for a while, have seen posts of fires. We have seen both videos of fires as they have occurred and pictures of the results of those fires. There is one especially illustrative view of someone using a camera to monitor their Glowforge while cutting the Eiffel Tower. The user gets distracted and the video shows about 30 seconds or so after the user stops paying attention to the Glowforge the first flame starts up. About 30 seconds later, the user is alerted to the fire by the glass top shattering due to the heat, if I recall correctly.
I have lost count of the number of belts, heads, fans, and cables I have seen photos of after a fire. From little flare-ups that aren’t so little that char the belts and fans and coat the lenses with soot to full out melted crumb trays, broken lids, and melted cases.
This unit isn’t the toy that a lot of users like to think it is. It is only as safe as the user and leaving the unit alone isn’t safe. I won’t even leave it alone while engraving stone or glass, even though that is about the safest one can get for fire danger. If I am cutting or scoring I am watching it the whole time. If I am engraving something flammable I have eyes on the contact point at least every 5-10 seconds. For slate, I am in the room and looking at the unit every 30-60 seconds. Just to make sure everything is OK.