This is a follow on bug from bug 480065, comment 29. Steps to reproduce: 1. Open the browser on a clean profile - no extensions at all. 2. Open the error console 3. Put this in the text field: Components.classes["@mozilla.org/preferences-service;1"].getService(Components.interfaces.nsIPrefService).resetPrefs(); 4. Click "Evaluate" = Expected = Nothing much should happen. = Actual = All CSS Styling in the error console window is lost until the next reflow. Specifically, the buttons transform to normal text. (resize the dialog, and the styles will come back). Boris' comment: OK, using Clint's steps I get a regression range from 2008-12-04-02 to 2008-12-05-02 on trunk. This doesn't match the regression range when bug 445004 landed on trunk. = Notes = This seems to be a mac os X only bug. On windows, nothing unusual happens. On Linux, session store throws an exception because it can't get a preference. However, the CSS Style remains intact. I'll open another issue for the session store error.

I suspect the user font stuff might be relevant here... some of it certainly landed in that range.

Is this a problem on both mozilla-central and 1.9.1 , or just one of them?

(In reply to comment #2) > Is this a problem on both mozilla-central and 1.9.1 , or just one of them? Both, latest builds.