Incredible extension. Not only does it deliver on its promise of tree-organization for tabs, but it also keeps up with other Firefox features like container tabs and even tab hiding! There has clearly been a lot of love and thought put into this extension to not only make it usable, but to make it feel like a native Firefox feature instead of a third-party extension. Its customization options are fantastic too, including the much-appreciated ability to tweak its CSS. Great work all around.

One Missing feature: New Tabs always on top of the tree, not at bottom of the tree (be the first one!).

Piro’s TST solution is working well for me.

What I wanted is a visual way to capture my trail as I browse, and that’s what it does. Attempting to try to turn it into tab organizer tends to lead to frustration. I find that a useful constraint—otherwise I’d be organizing tabs all day instead of researching things.

I put TST sidebar on the right, I use “Right side” style of contents, and RTL text direction. Even though I generally browse in English, the general alignment of things with these settings appears to work best for me so far.

I provision custom user chrome CSS in my Firefox profile (hopefully this keeps working) to hide the now-redundant default FF horizontal tab bar and TST sidebar header. I also used TST’s debug mode to tweak a bunch of settings and added bits of custom TST CSS to achieve the desired look & feel (samples in TST’s GitHub repo were a useful starting point).

I use TST with Conex, switching between containers and only showing tabs from currently selected container. I believe I had to fiddle with TST settings a bit to make it work together with Conex smoother, otherwise tabs within the same tree were opening in different containers. (I think it is not TST’s problem that with default settings visual hierarchy gets messed up if tab hiding is on.) In the end it’s hard to keep track of my tweaks and which of them are relevant as the extension gets updated, but it works nicely now.

I wish for an easy way to dump a tree of tabs into bookmarks while preserving the hierarchy in some way (even if it doesn’t let me restore the tree). The primary challenge appears to be that in Firefox a bookmark folder can’t itself be a bookmark, while in TST a tab holds other tabs.

I do encounter a situation where after Nightly’s update & restart, the TST sidebar never gets loaded. Just quitting the browser and opening it again fixes that. So far I haven’t lost tabs and never had tab hierarchy mess up on me, even though I was using pre-release TST builds from GitHub for a while until 2.4.20 came out.

useful replacement for the old tab groups extension. However, it's slow, and on every second addon update it mangles my tab groups.

EDIT: I take it back, it just fixed itself :)

Nice, really nice

Great Web Extension and only missing one star from perfect as occassionally it just seems to hang when FF is first opened with10 or more tabs opened. I then have to close the sidebar, restart FF then enable sidebar again.

Great job! This extension is most important for me.

Was looking for this for ages.
There's always space for improvement (bookmarking a tree w a single bookmark, hiding top tabs...), hope they/you keep up improving it. But it is best I've seen managing tabs - and I've tried several. Congrats!

awesome add-on with good information and howto make it better

PRO--
Vertical tabs provided by Tree Style Tabs is a wonderful idea. Despite Mozilla's rush to Quantum, at least Piror has provided a version that works (after a fashion) with FF Quantum

CONS--
1. Many of us who use Tree Style Tabs regularly have a great need for its companion extension, "Open Link in New (Tree Style) Tab". OLNT is available for pre-Quantum FF, and works fine, but is not available (yet?) for Quantum.

2. Under pre-Quantum FF, we could create a bookmark of all open TST tabs. Under Quantum, however, we are told Quantum has a bug which prevents our creating a bookmark without prior FF permissions, and are told to use the TST toolbar button to grant ourselves permission to create bookmarks. However, the toolbar button has no explicit control to grant permission, so we still cannot create a FF bookmark of TST vertical tabs.

3. Many of us expected that when we installed the Quantum version of TST, the top-most, horizontal tab bar would disappear, as it always did in pre-Quantum FF. But no-- the horizontal tab bar remains, for some inexplicable reason.

Very good idea but there are some issues with recognizing "pending" tabs. They should be red according to my settings (and it already worked for a short time) but they just keep the style of regular tabs. With over 300 open tabs, this is unfortunately not funny if you don't know which tabs are to be visited yet. With regular CSS and (userChrome) and FF tabs it works like a charm though.

When it works it's cool, but sometimes it just keeps loading and nothing happens! Now I have 3 tabs open and its been 25 minutes, still it is showing the loading animation, 25 minutes to load 3 tabs is not right. Very nice add-on but very buggy. The only solution is to close the tree style tab sidebar and then again click "show sidebars". Then it works perfectly. Hope its updated soon.