Words cannot express how awesome this plugin is (and has always been). I have been a TST user for many many years and it is the first extension I install on FF on any computer I use and is also the only extension for me that counts as a must have. It makes my browsing experience so much more richer and I am eternally grateful to the author for his continued hard work on this extensions (especially to port it to the latest FF which was no small undertaking).

Good looking and very useful, but quite the performance hog.
Its own Firefox process runs all the time over 20% CPU (why all the time???), at session restore needs like one minute to redraw... I keep like 300 tabs in 4 windows, so this looks like a limit. Yes I can kill its process then the tree disappears and the machine is fast again, but that's not the point.

Works great, helps me keep my tabs organized better than any other tab extension out there.

If you are trying to remove the tabs from the top, please try the code at my gist: https://gist.github.com/SgtPooki/3e4143de258563653fc4082b2ac0f886

Install this extension now.
Press F1 to toggle the tab sidebar - tabs are a "child" of the tab you opened a tab from. This means your tabs are auto-categorised and you can see the "history" of how you got to a page at a glance.

I was concerned this would no longer be available for FF57, but the author has re-written the extension, leaving it better than ever.

It fits new firefox design :D

Very useful. However too few options. I wish there's a way to one-click sort and group all tabs under same URL.

Great addon, but I wish it had some improvements. The trees are really handy, but when closing a tab, the tab I get moved to sometimes isn't the one right next to what I had open. And I rally wish this allowed you to tag your tabs after already having them open. Having to tag, duplicate, and close is a rather bothersome.

I've been using TST for ages now. I'm glad to see it's made the leap to Firefox 57, and it works really well here. Highly recommended!

Why are changes usually worse?
Why "Reload this tree" is in an additional context menu? It extends the work.

not visually attractive

An essential extension for those who open a lot of tabs. It is especially useful for grouping tabs from various sites.

It would really be helpful if it were possible to disable the tabs at the top of the page.

Well designed, simple, and easy to use. Beautifully integrated into the builtin Sidebars. Tabs are automatically arranged in a hierarchical structure and you can fold and unfold a parent item. I've only started using this minutes ago, but I already love this addon!

great, but now i have tree tab, the orignal tab bar is not nececery now, how can i make it disapear?

It's a very big UI flaw that I can't open my bookmarks or history up along side the tree tabs (as they are both stuck in a single sidebar pane). Please complain to Mozilla about this.