shift key is still blocking other keys

AFAIK, after base.mouseWatcherNode.setModifierButtons(ModifierButtons()) shift key is supposed to behave just as usual key. But it doesn’t. If you press any other key when holding “shift”, their events are not sent. In other words, if I walk on “w” and run on “shift” + “w” (not combined “shift-w” event, but two separate events), I can run only if I press “w” before “shift”.
This is very wrong, I guess.

This is discussed in this thread:
If you use messenger.toggleVerbose(), you’ll see that the event is still getting sent as “shift-w”, even though you have issued the base.mouseWatcherNode command.

I believe you have to set the modifier buttons to empty on the ButtonThrower object, as discussed in the referenced thread. That seems to work fine for me.