Extremely sorry for not updating the thread. Since the last Opera update you don't need this thread anymore. By default opera now opens extrnal links in multiple tabs and you can also set opera as default browser from Settings » Applications » Web » Default Browser For your current issue please 1) Delete the defaults.list and operamobile-labs-default.desktop you recently placed in /home/user/.local/share/applications/ using any file manager. 2) Then place below uploaded defaults.list file there.