This was only every implemented under X11, and with CSD,
this is clearly in the application realm. We should not
pretend that we can support it on the toolkit level.
https://bugzilla.gnome.org/show_bug.cgi?id=775061
The application demo had a "Blue" and a "Bold" menuitem both with
the Ctrl-B accel. This is confusing, since only one of them works.
Change the accelerator for bold to Ctrl-Shift-B, so they both work.
Change the format of GtkBuilder <menu> to be more in-line with the style
of the rest of GtkBuilder so that we can do translation in a consistent
way.
The format is now substantially more difficult to hand-write, but tools
should be along soon.
There is an xslt program attached to the bug to help you convert your
existing .ui files from the old format to the new one.
https://bugzilla.gnome.org/show_bug.cgi?id=668696