The edit button is grayed out in diskdruid, after going back to change
partitioning method, and arriving again in diskdruid, doubleclicking
partitions to edit still works.

Here's an easy way to reproduce it:
-choice gnome workstation install
-choose manual partition
-remove all partitions (dunno of this is needed to reproduce it)
-go back to install type choice screen
-choice gnome-workstation again with fdisk selected
-run fdisk once (I just did q immediatly afterwards)
-now in the diskdruid screen you the edit button is grayed out no matter
 what partition you select, but doubleclicking on a partition to set the
 mount point works fine.