Rated 5 out of 5 stars

Folks 1.61 beta IS available and works with FF 9.0
Scroll down to the bottom of the page, select the chevrons in the VERSION INFORMATION section to expand it. Select SEE COMPLETE VERSION HISTORY link. 1.61 beta is there, hover the mouse of the title VERSION 1.6B1 and the ADD button shows.

This review is for a previous version of the add-on (1.5.4.1-signed).