Settings and driver store no longer sit on a strip of their own: while
open but inactive they append to the focused group's tab strip (v0.6.2
order), and while active the app-level strip re-renders the open tabs
with mode icons and inactive styling as the mouse path back to the
editors. Special tabs follow the classic/separated presentation,
including the classic active underline.
Opening settings or the driver store hid the whole workspace, so every
editor tab vanished with no mouse path back. The workspace now stays
mounted and hides only the pane content, keeping the strips clickable.
Special-page tabs also follow the classic flat tab presentation instead
of always rendering as separated-layout pills.