Hello,
Started a new multiplayer map a few days ago. This error did not occur when I started the map but when people joined later - toggling the highlighting off seems to stop the error.
22001.760 Script @stdlib/stdlib/core.lua:45: ...kerBeltTools__/scripts/belt-highlight/belt-highlight.lua:820: attempt to get length of local 'input' (a nil value)
https://imgur.com/a/UpuuGuX screenshot