On Tue, Jul 29, 2014 at 9:51 AM, Daniel Cheng <dch...@google.com> wrote: > 1) The frames attempt no synchronization and both just call > requestFullscreen(). In that case, the observable difference is largely > moot. It shouldn't be surprising that racing operations like this cross > origin returns a non-deterministic result. This is the position the Chrome > out-of-process team is taking for other sorts of actions that have effects > visible outside the frame (for example, navigating the top level frame, > multiple frames sending a postMessage to the same frame, etc). > > 2) One frame calls requestFullscreen() and then sends a postMessage() to > another frame, which calls requestFullscreen() upon receiving the message. > Going fullscreen requires coordination with the browser process, so ordering > is preserved by browser IPC message handling.