I decided I couldn't quite submit a gimp-brainstorm item with this
TAB normally toggles the visibility of the docks, including toolbox.
In single window mode it doesn't (and IMO it would be good if it did
-- single non-fullscreen window is a lot more cooperative with other
app windows than simply toggling fullscreen is.).
I wanted to mention that in case it was simply overlooked rather than difficult.
Looking at the code in display/gimpdisplayshell-callbacks.c and
widgets/gimpdialogfactory.c, I found it difficult to tell.
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