Rated 5 out of 5 stars

bởi Firefox user afa19a vào Tháng 12. 5, 2017 · liên kết thường trực

Due to changes in the Firefox API, this add-on cannot be made compatible anymore for Firefox 57 and above. Best alternative is to reinstall Firefox 56 and to disable automatic updates.

https://www.wikihow.com/Downgrade-Firefox