A few days ago Firefox started acting up, rendering some sites incorrectly. Have a look at the attached screenshots. 'Screenshot from 2013-12-27 13:12:33.jpg' is how Firefox is displaying a page from theguardian.com, and 'Screenshot from 2013-12-27 13:18:57.jpg' is how Chromium is (correctly) displaying the same page.
I've been having internet connection speed issues lately. Is that somehow the cause of the display issues? I know switching to Chromium full-time would be a solution. But I've been using Firefox for years and would prefer to stick with it. So, is there a solution to this rendering problem that doesn't involve switching browser?