Hi.

The display unit in mm is a good option for printing and anybody can change using a template or modifing the default one.

Maybe a prompt when change display units to retain current scale could be a good option, I always need to change to previous scale (normaly 1.00) once change to display_units.

Also I add a option to resize to content, what I retain collapsed by default, to make the same value in 4 inputs.

Regards, Jabier.