The mod Belt Balancer 2 (2.0.9) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event belt-balancer-2::on_player_mined_entity (ID 68)
belt-balancer-2/objects/part.lua:265: attempt to index local 'belt' (a nil value)
stack traceback:
belt-balancer-2/objects/part.lua:265: in function 'remove'
belt-balancer-2/control.lua:145: in function <belt-balancer-2/control.lua:134>

Happens when trying to move/pickup the belt balancer after it seemingly glitched out, even roboports can't move it.
Am able to add+remove more belt balancers around it except for the bottom side.
Attempting to connect an input on the bottom side causes it to crash. Happened on fulgora.