almost perfect Rated 4 out of 5 stars

It doesn't play nice with the page title addons because doesn't paint the separation line between the domain and the title (https://addons.mozilla.org/en-US/firefox/addon/page-title/?src=api).
Your fxopera works with this addon right

This review is for a previous version of the add-on (1.3.4).  This user has 4 previous reviews of this add-on.