I am doing a lot of very thin acrylic work, and have sussed out how to change the tab dimensions when cutting a path. I like 4mm long and 0.5mm thick. But the idiot operator forgets sometimes and the pieces he cuts with the default tab settings do not break cleanly and crack either side of the cut. Not good
As I understand it tabs are a part of design.
GRBL only does what it is told from the design.
There used to be an issue where the tabs were not carried over when an item was copied. Not sure if that still exists.