This would be a rather small feature to add, but I can see some value in the option to change the default start value of a group box (either start expanded or start collapsed) in an expression. I have run into a few situations where it would be nice if I could set a group box to start collapsed if the inside data source is empty or start expanded if there is data. This feature could possibly be added to other similar widgets as a way to potentially speed up apps and create more dynamic page layouts.