The mod Belt Balancer 2 (2.0.9) caused a non-recoverable error.
Error while running event belt-balancer-2::on_configuration_changed belt-balancer-2/control.lua:35: attempt to index field 'belt-balancer-0' (a nil value)
stack traceback: belt-balancer-2/control.lua:35: in function <belt-balancer-2/control.lua:25>