I don't think that's completely unfair to say that the UI is not as responsive as it really should be, I would suggest two things: 1) look around on http://pla

I don't think that's completely unfair to say that the UI is not as responsive as it really should be, I would suggest two things: 1) look around on http://planet.mozilla.org http://planet.mozilla.org https://wiki.mozilla.org/Performance https://wiki.mozilla.org/Performance etc. people are working on UI-specific performance issues (commonly called "jank") 2) try the UX branch builds for the latest UI which is coming soon - https://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/latest-ux/ https://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/late... Progress is being made, but it takes a while to hit the beta/release channels. It's pretty critical that such improvements don't cause stability/security/standards problems too so they're not the simplest of changes!