When viewing an article with an embedded YouTube video (maybe others?) in the browser view mode, if you start the video, then switch to full screen mode, the video will play for about a second then disappear, along with the browser view. Once back in the article browsing mode, the article window will no longer work, even when switching articles. As far as I can tell the only fix is to force quit the app then restart.
Strangely enough, full screen youtube videos work just fine when not in the browser mode.