A change in architecture is a major change and one of the consequences of implementing e10s is that there are add-ons that are not compatible with it. Add-ons that are not compatible right now are among others Adblock Plus, LastPass, RequestPolicy, Greasemonkey, HTTPS Everywhere, BluHell Firewall or Video Download Helper. Mozilla keeps track of add-on compatibility with e10s on the Are We e10s yet page*. Here you find bugs listed that you can follow to find out if progress is being made to make the linked add-on compatible. Many popular add-ons have not been tested yet, with the page only listing some of them. * arewee10syet.com/
