toplevel .t
ttk::menubutton .t.test -text "Foo"
pack .t.test
The right third of the drop-down arrow indicator is cut off.
When moving the mouse over the item, highlighting shows a very narrow vertical slice being allocated for the dropdown half.
Only happens with XP and Vista themes on Windows 7. Does not occur under XP, have not tried Vista.
Tried playing with layout and padding in both TCL and C (ttkWinXPTheme.c) without any effect.
screenshot of bug
This was fixed following 8.5.8 release and is fixed in the current 8.6 HEAD. (See commit of 7 Oct 2010 for bug #2787164