&gt; This is definitely not always the case in my experience, although that might be due to some addon (I have quite a few) hanging the main FF thread&#x2F;process.<p>My experience matches yours.<p>I think chimeracoder means that&#x27;s the way Firefox works <i>if</i> e10s is enabled, which wouldn&#x27;t be true for you unless you&#x27;ve explicitly done so. (I haven&#x27;t enabled it either)