Rated 4 out of 5 stars

Nice challenge, nice work; but wouldn't it have been simpler (& easier) to leave the switch button as an icon on the toolbar and have it flash for instance when applicable? That would prevent any issue on pages ...

This review is for a previous version of the add-on (0.6.7.1-signed). 

Yes it is. But this is simpler (& easier) for user and that a point. Issues on some pages i always try to fix, when users tell it to me. Thank you for feedback.