ALL textFrames AND/OR Rectangles of the GROUP - ofcourse :-)_
Precisely define "empty" ;-)
My smiley indicates some irony here, but one never knows, what is considered "empty" when it comes to text frames and rectangles.
he, he You are absolutely right : EMPTY not always mean "empty" :-)
TextFrames: there is no even one letter inside :-)
Rectangles: there is no associated File in the Rectangle
So you consider a rectangle filled with a color as empty?
Same goes with text frames?
Is text whitespace considered "empty" ?
See, the discussion has just begun ;-)
You should really search the forum here.
We already had a splendid discussion some years ago what is considered "empty".
And I think Colin Flashman https://forums.adobe.com/people/Colin%20Flashman attempted and finally worked out a cool function for "emptiness".