I’ve just Googled my way to this page because I too couldn’t figure out how to edit a Group. The wording and location of the “button” make it look like a subheading, not a button.
The crude fix would be to change the word to “EDIT GROUP OPTIONS”, but even then I don’t think it’s obvious. Better option would be to inline the options into the main window and get rid of the button altogether.
PS: I’ve voted for the feature request, although I’d call it a usability bug.