Ender3V2: Extruder stepper stops mid-print

[minor atlas]

After 10 hours of printing, I noticed the nozzle was flying in the air, without anything coming out.
I saw that the extruder gears were not spinning at all (so it wasn't grinding). The nozzle was also still at temperature, so that also wasn't the problem.

I pushed the filament down, and noticed that I could do so without any resistance at all. The gears also spun when I pushed it down. The stepper must have powered off for some reason?! All the others were still working fine though...

I powered off the printer and plugged it back in. This time the gears are locked again, which means the stepper is getting power. When manually extruding I saw that the gears tried to move half a degree before going back to the powered-off state where I could freely move the filament.
I repeated this behavior several times. Shutting down the steppers through the buttons gave the same result.

Anyone know what went wrong here? Is my stepper and/or driver broken? =/

[twin rapids]

Which board and drivers? If they are removeable you can try to swap E with any other Driver and check if the problem wanders with the driver. Else you can swap steppers. In any case i'd check Vref and measure stepper coil resistance.

[minor atlas]

I think the default boards. I never changed them. I'll have a look when I get home.

[blazing rock]

Possible overheating or a corrupted sdcard /gcode