I just ran into this. I have a 2GB limit on my data and my usage was running high this month. Didn't understand why but I had been travelling so I thought maybe I had used that much data. Today I was notified I hit the limit for the month while I was connected via wifi (or so I thought) and still have a week to go before it resets. Installed Opera a couple weeks ago. I just disabled Opera from being able to use cellular data and will try it again when I get some more data credited to my plan. If that doesn't work, I will be uninstalling the app. GRRR. Fix this issue !