* Fix #1757772 tempo, dynamic related plug-ins bug -- make auto-align only auto-align if there is a unit involved * Fix #1755366 text layer bug in retrieved session * Fix input model selection in plugin parameter dialog (was being ignored) * Use lighter background than the standard widget one for panes (assuming the widget background is light but not white) -- similarly darker if dark * Fix colour reference counting in loaded session in SingleColourLayer * Reset overview pane colour when switching dark background on or off