Not sure if its related to the fact that focus mode passes clicks to the panes beneath it, but expand and collapse just dont work. When you hit any of the expan and collapse icons, the focus window just collapses and comes back to the overall board.
Also probably related, when you open focuse dmode and you have the board toolbar on the left side, the screen is still responding as if the toolbar was active.
Anyway bringing this back on the list to be prioritized. I so much want to use focus mode for some things that right now are supplied by the popup mode, but these bugs need to be fixed for focus mode to be useful. Before that, it just doesnt work for me.