Latest Firefox update massively improves Adblock Plus memory usage. Issue involved Firefox creating too many so-called style sheets for Adblock users. Firefox now uses about the same amount of memory whether youre running ABP or not. Mozilla developer Nicholas Nethercote was the one who spotted it on his blog and blogged about it in May. Back in May, Nicholas noted that most people, including himself, will gladly use extra memory in order to block ads”]
Source: https://adblockplus.org/blog/latest-firefox-update-massively-improves-adblock-plus-memory-usage