Sticky notes is quite practical, but it happens easily that text gets deleted by accident. Thus some form of undo (ctrl-z) would be very helpful.
Longstanding feature request consequently ignored by gnome devs: https://bugzilla.gnome.org/show_bug.cgi?id=305654
This is hard to implement because Sticky notes uses GtkTextView, and it comes without undo support. I think we need to check if we can replace that control with another one with undo support.
I guess that would be GtkSourceView. http://projects.gnome.org/gtksourceview/
Another approach might be to look at some existing lightweight editor like leafpad and reuse its undo support. http://tarot.freeshell.org/leafpad/
stickynotes: Add undo/redo feature
Using GtkSourceView instead of GtkTextView
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