Comment 64 for bug 109943

(In reply to :aceman from comment #35)
> Does anybody still see this? With TB32, in Win XP I can't see the high CPU
> usage any longer. Via DOM Inspector, in TB main window
> (chrome://messenger/content/messenger.xul) I found <statusbarpanel
> id="statusbar-progresspanel"> where I set collapsed="true" to uncover the
> status bar progress meter. Then in <progressmeter id="statusbar-icon"> I set
> mode="undetermined". The progress bar began spinning without much CPU usage.
> So the progressbar alone doesn't seem to be the culprit. If we can find the
> CPU usage in other scenario, maybe something else is contributing to it.

I seem to be getting conflicting data here. I did the same on a fresh profile and CPU went up to nearly 20%. The same happened when I used DOMi to add a new progressmeter element without any eventlisteners and such connected to it as long as the mode is set to undetermined. In fact, it even reproduces in Firefox nightly for me when I do the following in browser console:

var parent = window.document.getElementById("urlbar")
var progress = gBrowser.ownerDocument.defaultView.document.createElementNS("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul", "progressmeter");
progress.setAttribute("mode", "undetermined");
parent.appendChild(progress);

Could someone confirm that last bit to make sure it's not just me? If so, then the only thing Thunderbird can do is to work around by not using undetermined mode at all..