I'm using Ubuntu 14.04 LTS on my laptop with an external monitor connected to it. My setup is such that the laptop screen is on the left and the external monitor is on the right.
Now, whenever I right click on the left half of my 2nd screen i.e. the external monitor, the menu shows up on the right edge of the 1st screen i.e. the laptop screen.
If I right-click on the right half of the 2nd screen then the menu shows up correctly. Refer screenshot 4.
I am using Google Chrome (Version 46.0.2490.71). Right-click works fine in Firefox and other applications.
Screenshot 2: Link
Screenshot 3: Link
Screenshot 4: Link