It seems that this layout will cause the input method methods to be
called, whereas "normal" layouts don't go this route. The problem is
that this sends the wrong text (namely a ',' in the case when the user
pressed 'w'). However, we also need to set the
"interpretKeyEventsSwallowedKey flag since in this particular case we
really mean that a selector didn't swallow this key.
Yes, it's complicated and this layout is used by a very small minority.
But this layout is handy enough to support, kind of like the Mac users
of old. :-)