I’ve got a roll of Blue Geeetech ABS+ that starts to smoke when it’s still so cold that its layer adhesion is terrible, and just burns in the nozzle whenever it’s not actively extruding if the temperature is high enough that it sticks to itself. Obviously, this is bad, and it sooted up a nozzle so badly that it needed to be replaced before I gave up on it.

So far, the only ideas I’ve had are just to leave it on a shelf indefinitely or to landfill it, neither of which are a great use of nearly a kilo of plastic.