Because the rest of the commentors in this thread seem to not be reading the article, there's a performance issue in Firefox due to the following unresolved bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1190398
I wonder what exactly is Firefox dev team spending all that time saved by not fixing peformance issues such as the bug linked above.
Chrome seems to be doing some things right and Firefox is just adrift...