This is often called "global scope pollution" and is defined in the spec at http://www.whatwg.org/specs/web-apps/current-work/#dom-window-nameditem. I believe that in Firefox 4 you should only be seeing this behavior in quirks mode.
There is a bug on file at http://www.w3.org/Bugs/Public/show_bug.cgi?id=11960 to change the spec to match the Gecko behavior, where this occurs in quirks mode only. - Kyle On Fri, Apr 1, 2011 at 3:26 AM, Alexandre Morgaut <alexandre.morg...@4d.com>wrote: > > My biggest nightmare today is that recent browsers like Chrome, IE9, FF4 > generate a global variable from the id of each HTMLElement of the > document... > >