Don't forget to disable the old non-working AutoPager addon!
AutoPager automatically loads next pages when you reach the end of a page. It works on a ton of sites,Google,Yahoo..
It works well with most other add-ons adblock plus, WOT and most of the greasemonkey scripts.
You can also try AutoPagerLite.
The original author apparently isn't available on the Net for quite a long time and the support forum domain wasn't even resolving for half a year (the web archive's last record is 2014 June). Meanwhile, Firefox 36 is already used by many people... Thankfully, fixing the addon was very simple. The only two issues, mentioned in the FF36 addon compatibility changelog, that needed fixing were the new 'const' semantics and an nsITreeView's get***Properties props parameter.
DISABLE THE ORIGINAL AUTOPAGER ADDON!