Keep door open if player is still in trigger box

the file you provided on Oct’22 clearly features a script with RunContext = Legacy, and it resides in the Workspace, therefore, by default, it will be run on clients; UPD: my mistake, Workspace only runs server-side scripts (BUT storing any kind of scripts in the Workspace is a bad idea bc they easily get replicated to client memory stack)
and, by the way, I’ve already encountered desync with it being run unfixed - doors stay open on one client while being triggered for closing on the other; that is a clear indication of workspace geometry being manipulated on the client-side, which is unrecommended