I'm printing a Tower of Pi on my Ender 3, and I woke up to find this near the extruder:
All my attempts to google this led to checking for either a clogged nozzle or the extruder itself stripping the filament, neither of which appears to be the case.
It looks like the upper edge of the filament might be grinding against the intake hole, so I looked into lubrication, but the consensus appears to be "don't".
Has anyone else had this problem? Is there a name for it, and how do I fix it?