It strikes me as odd that resetGestureRecognizer is called in WebFrameImpl::createFrameView...this is called for every subframe of a page, and for subframe navigation too! Here's a scenario where I expect this might break: You have a rotating ad (the iframe navigates to a different page every few seconds), and on every navigation WebFrameImpl::createFrameView is called. Suppose you're in the process of doing a pinch-to-zoom gesture, and the iframe's src changes during that gesture. Now the gesture recognizer will get reset. I haven't confirmed this actually happens but I suspect it might. I am currently in the process of refactoring WebFrameImpl::createFrameView().