I use PanoramaTabGroups to split tabs into groups. When closing tabs to the right, this add-on removes tabs from all groups, not just current. If you add 'skip invisible tabs' option, I'll upvote to 5 stars. As is, this add-on is useless for my needs.

THANK YOU!!!! Working!

Firefox Quantum 以降で使えるこのようなアドオンを探していました。有難うございます。

It even works on Firefox for Android!

thank you for creating this magic thing ! Save me a ton of time.

Really what I needed: simple, useful, working.
Great work, thanks

Thank you very much for updating! A very needed extension!

simple,but a great addon.
works fine on FF59beta
not works on FF52ESR though.

このために57へのアップデート待ちしてました有難うございます！！！

These simple buttons are so great, I painfully missed them when Firefox Quantum was released. Thanks a million!