Thanks, J.A.! If the multitask bar is what I get by doubleclicking the home button, yes, that's when it appears. I never noticed a randomly selected thumbnail there before; I thought it was a thumbnail of the page that was open. Anyway, since I've already restarted a few times, I did a reset...

i have an iphone5, unmodified. While using safari with several tabs open, one tab got confused and the landscape/portrait orientation got stuck. So the image and screen controls were in portrait with the phone oriented in landscape and vice versa. I could not use the page controls and the area...