[Solved] What are these panel decorations for?

It’s a shame, but I can’t figure out what these panel decorations are for! I have clicked, double-clicked & right-clicked them, but I have observed nothing interesting. I have even tried to drag them! And I don’t know how to Google for… that.

You know, right? Please, share.

Drag a panel tab and release it above one of the small squares to change to ui layout.

Oh, nice! A GUI element whose purpose I didn’t understand and a GUI feature I was missing, both problems solved at the same time. :slight_smile:

Thank you very much!

Formerly it’s the Placement Widget