Rated 5 out of 5 stars

by impact0r on Nov. 20, 2019 ·

You can still use that extension if you run Thunderbird 60.
If you are on Linux, and regular install (downgrade) wont' work due to broken libraries, you can install Thunderbird 60 through snap:
"sudo snap install thunderbird --beta"
If you are not on Linux, think about what you're doing with your life.