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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

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!

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?

Very useful, clean and light weight. Also, an excellent port to the new firefox infrastructure.

Great extension - allows for really intuitive organization of tabs.

Wonderful!
There used to be a "Search Tabs" feature. Is it possible to bring it back?

The best tree-tabs add-on. Long time user (~5 years) and I like the migration to the web-ext. The only ask for firefox developers is to put an API to hide the old tabs bar so that it can be used by add-ons like TST. Currently I am hiding the tab-bar from the userChrome.css.

Shameless plug: I have written the load-progress-bar add-on to give me a little better idea about the page load progress that I am missing in the new FF57 and I find useful in combination with TST

One of the main reasons I choose Firefox - this makes it easy to maintain separate workspaces for different projects, and to keep track of a lot of tabs. Incredibly useful

10/10 !

to hide the usual tabs, and to hide title bar of TreeStylTab

[your firefox profil folder] /chrome/userChrome.css
--------------------------------------------------------------------
@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul");

#tabbrowser-tabs { visibility: collapse !important; }

#sidebar-header {
display: none;
}

Great when juggling multiple tabs. A must have! Easy to use without any issue at all. 5* from a satisfied customer.

This extension has changed my life. My work can involve juggling many web pages, whether I'm maintaining issues in JIRA, Writing pages in Confluence, filling in timesheets, or any number of other things. So many mistakes used to happen when I had 3 copies of the same page open at the same time and editing content in 2 of them at once without noticing. But no more! All my pages are now organised in a way that actually mirrors the way I'm working. This is a browser extension that makes me smile! :-)

This is one of the extensions I can't browse without after trying it for about five minutes!

It's just perfect for maniacs like me who tend to have at least a dozen tabs open at any time. Especially at work where I like to have the complete trail of websites visited while researching the latest technical problem(s) available and organized.