Error while running event toolbars-mod::on_player_main_inventory_changed (ID 35)
...sections/section/content/table/slots/item/ItemButton.lua:31: attempt to index field 'elem_tooltip' (a nil value)
stack traceback:
...sections/section/content/table/slots/item/ItemButton.lua:31: in function 'new'
toolbars-mod/src/gui/Component.lua:144: in function 'loadChildren'
toolbars-mod/src/gui/Component.lua:132: in function 'load'
toolbars-mod/src/player/Player.lua:72: in function 'load'
toolbars-mod/src/player/Player.lua:47: in function 'get'
toolbars-mod/control.lua:84: in function <toolbars-mod/control.lua:83>

The error occurs if you delete a mod, any entity from which is present on one of the toolbars.

what is the workaround

Clear slots with items from those mods. Save game. Disable mods. Load game again.

Clear slots with items from those mods. Save game. Disable mods. Load game again.

Of course , did it already

It wasn't obvious to eternal_wait to who this answer is addressed.

:))) ok. thanks :)