Setting nb boards to 0 => no more tab button

[Light_user]

When changing the default button (tab view) board to '0' (deleting is not possible) and adding 1 button board in window mode, you can't change any setting anymore because there is no way anymore to access the settings option. And on the window button board, you cant edit the button board anymore, nothing happens when clicking the menu.

[Niffo]

Please quit and relaunch the software. We will do something to prevent this kind of thing (this is also why the first tab can not be a window )