i hope it could be pinned

Search is absolutely terrible! It doesn't find the tabs properly.

Looks like it would work, but the shortcut doesn't open it on macOS Big Sur with Firefox v89.0.2. Hasn't been updated in 3 years.

Rich but rather complicated keyboard shortcuts system is sole reason to prefer the extension over tabFx. If mouse use isn't a problem tabFx is much more flexible.

How about adding a close tab option to each tab while in view tabs mode: point and click!