Does anyone found a solution to this?
I am facing the same problem.
I have disabled contextmenu, but after user selects a text, on right-click "copy" menu is visible.
I was looking for a solution to the same problem and found only this thread.
After a few tests and researches I've found how to do this and it seems to be fairly easy.
To avoid selecting text an element should have css attribute "-webkit-user-select" set to "none" (this is WebKit's equivalent for css3 user-select). The only thing left to do is to set cursor's shape to "default" or "pointer".