Setting focus to the address bar using a firefox extension

I'm developing an extension that requires to set focus to the address bar at some point. I've been trying to RTFM, but the FM is开发者_如何转开发 so hard to read!

Does anyone know of any way to set focus to the address bar from within a firefox extension?

TIA.

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I would imagine it would be something like:

var addressBar=document.getElementById('urlbar');
addressBar.focus();

assuming document is in the XUL Chrome context.

I haven't tested that yet though, so I'm not 100% yet.