The one reason why Firefox is so slow: XUL. Has anyone noticed that other browsers using Gecko as their rendering engine (Epiphany, Galeon, etc.) are much fast

The one reason why Firefox is so slow: XUL. Has anyone noticed that other browsers using Gecko as their rendering engine (Epiphany, Galeon, etc.) are much faster than Firefox? AFAIK, these browsers are built using native toolkits (GTK+ for both Epiphany and Galeon) of whatever platform they work on. Also, has anyone noticed how slow Songbird is? That's XUL for you. I don't care about extensions. IMO, a web browser is supposed to let you view and interact with webpages, nothing more, nothing less. Leave the ad blocking, note taking, email checking, photo uploading, iTunes controlling to separate applications. How difficult is it for Mozilla to just wrap up Gecko in a Cocoa shell for the Mac, GTK+/Qt shell for Linux and whatever toolkit is used these days on Windows? Why build the UI using XUL? I'm an Opera user, but I hate the way they've been piling on feature after feature into the browser. BitTorrent? Speed Dial? If they don't stop now, I'll switch to something leaner.