Works great! However, does not seem to work in Private windows, would be great if it was fixed.

Does what is says. Pretty useful. It's no longer in development I think but I wish it also did:
-Custom sorting (e.g. "put example.com tabs at the start regardless of alphabetical order")
-Sort by container tabs

Works great! Would love to have a custom sort function possibility.

sometimes does not work but anyway it is a good add-one

Update: I still love and use this addon. However, it needs to be made compatible with the new Firefox tab groups. When sorting, all tabs get removed from their groups and the groups are discarded.

Original review:
Way, way better than SortTabs. It is incredibly faster when you have a ton of tabs (I regularly have over 1,000 tabs as I study a ton) and does not have any intrusive required permissions–just access to browser tabs and that's it!

Love it.

Nice add-on, but does NOT 'sort by URL'.

"Sort automatically" does not always work. If this gets fixed it's a 5 star addon!

It works fine, but for some reason, it does not remember the setting when firefox closes, each launch, I have to 'refresh' the setting. Other than that, it works.

Works fine. But would be great to be able to exclude pinned tabs, as I don't want my pinned tabs to be affected...

The addon is useful and sorts by one of the various criteria available(which seem sufficient) stated in the description.
However it also sorts pinned tabs, which in my case is an inconvenience. Great addon overall.