Baffled

Hi all. I've had something baffling happen for the last week or so. When I open my browser, Opera, and begin to type in the address bar, it comes up with nonsense, not in the least like anything I typed.
I haven't made any changes or downloaded anything lately, so I have no idea what is going on.
Can anyone suggest a cause and hopefully, a solution please? (Using 8.1)

Baffled