Turns out we didn't really have the right-click bug under control. I went through the code with a fine tooth comb and found a weird edge case where you could trigger the error when dragging nodes while deleting them (pressing the delete key). That would mean you were essentially dragging "ghost nodes", causing the system to freak out.
In the new release, "ghost nodes" are now simply ignored, avoiding any error pop-ups.
As always, you can find the new release on the downloads page.