Not working in FF 128.5.2esr 64-bit : Don't get an Icon to click nor a possibility to add an Icon to the "Customise toolbar". From the options seems to be what I need, but can't use it !

doesnt work.

DOES NOT FUNCTION! Update required for newest 64 bit Firefox.

Not working in Firefox in Windows 10 pro

I would love to give it 5 stars but it does absolutely nothing. Tried multiple email clients + webmail options / reinstalling / restarting. No success. (Manjaro) :/

Works with Thunderbird and does what I need. It adds the word "interesting" before the URL, and I was going to complain about that. But you can easily configure it as you please.

update in May 2021. Doesn't work.