You have to remember that Firefox's core was first written in a very different era of computing. E10s required a complete rewrite of really core components for

You have to remember that Firefox's core was first written in a very different era of computing. E10s required a complete rewrite of really core components for Firefox. It took years to get it working, and it turned out to be impossible to make compatible with existing extension code, etc etc. FWIW, give a try to Firefox with E10s, or better yet, firefox developer edition. I find it much faster than chrome.