That happens when content on the page hasn't finished loading yet. In this case your browser is having difficulty communicating with Google Analytics' servers (you can see it's trying to connect in the bottom left of the screenshot), which Bungie.net makes use of with a piece of Javascript in the bottom of the page. It shouldn't interfere with anything since it loads asynchronously to the rest of the page, but you can always use an extension like AdBlock Plus to disable GA.