Rated 4 out of 5 stars

Nice. New features a bit buggy. Sometimes hover play doesn't work.

This review is for a previous version of the add-on (1.1.1-signed). 

If you give me a link to a page on which it fails I can take a look. (email: simon.lindholm10@gmail.com) I know it doesn't work on background images, unfortunately that's unfixable. :(

(Edit: Tumblr should hopefully work better in the latest version.)