Why do people keep saying they got rid of XUL? It's just not true. It's still there to this very day. Just look at browser.xhtml (the main browser UI file); it'

Why do people keep saying they got rid of XUL? It's just not true. It's still there to this very day. Just look at browser.xhtml (the main browser UI file); it's a mix of HTML and XUL and the body tag is particularly interesting. <html:body xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"> The first child element of that body is currently: <popupset id="mainPopupSet"> That's not HTML ;) They are trying to replace XUL with HTML and made some progress towards that. For starters they removed most or all of XBL. From the perspective of an add-on dev it wouldn't have made much of a difference, it used to be manipulating a XUL DOM, now would have been manipulating a mixed XUL/HTML DOM, in the future it would have been manipulating an HTML DOM, not much difference except for tag names and attributes names really, and the rest was js and css.