I didn’t know this … just ran into the feature just now … maybe it’s been there since the beginning.
In the list of subscribed communities … hover the mouse over the icon of the community … a star will appear, unfilled if not a favourite, filled if already a favourite … and click to toggle.
All “favourite” communities will appear at the top of the list in a separate section.
Very nice!!
Oh right, I don’t think I ever announced that. I’ll add it to my recent announcement post!