I've had a problem recently. That is to say, the past few weeks I think, I didn't quite keep track.
Anyway it's becoming quite a nuisance. You see, while browsing, and what seems to be at random, Opera will completely stop responding to keyboard input.
Actually that's not true. Sometimes, I can type text in the address bar and generally anything in the top part of the screen. For instance, I was able to press F11 for fullscreen while my mouse was up there, but not otherwise. Curiously, this didn't work in one window, but did in another.
My only clue to this problem is mouse gestures. You see, gestures also stop working. I'm often able to pull off the single direction ones, such as open Speed Dial (down), but not close tab (down, right) which is the one I use the most. I also noticed the problem generally occurred after I had been closing multiple tabs this way. This would also explain why it affected one window more than another, as one of them apparently locks up in a gesture or something like that.
At one point, I was able to reset this issue by re-plugging my mouse, but usually it requires a browser restart to fix.
Another thing that may be worth noting is that I keep a massive amounts of tabs open across multiple windows. I rarely run out of memory though.
So does anyone have similar problems, or better yet, a solution? I'm going to assume it's only present in the current version, which for me is the latest beta. I realize this means I should expect issues, but it's been good to me so far.