9d7d52c1de
Depending on the number of windows, the button either shows the title of the lone window, or the app title for multiple windows. While we always recreate the single-window title, we only create the app title once and hide it as necessary. Avoiding re-creating a simple actor 50% of mode transitions isn't worth the additional complexity, so just handle both single- and multi-window titles the same way. Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell-extensions/-/merge_requests/337>