I think this extension is the best replacement for Tab Groups.

To make this ideal, I need a keyboard shortcut to cycle groups (Tab Groups had Ctrl + `), and to be able to hide the list of tabs while showing the list of groups, (or have a separate dropdown menu of groups on the toolbar).

But it works well and I've found it more intuitive than alternative extensions. Thanks!

Fantastic extension.

Vertical tabs in sidebar is so much better than unreadable horizontal tabs. F1 to open the vertical tabs. Only use Folder feature. You can open and close folders and sub-folders to keep the list manageable.

When you close Firefox and then reopen, your vertical tab list reappears. Perfect. No performance hit.

You can get rid of horizontal tab toolbar using userChrome.css. google it.

Dont know what Groups and Sessions are used for.

This extension makes Quantum worthwhile. But I still need a NoScript replacement.

I GOT SO MUCH MORE THAN I WAS LOOKING FOR with Tree Tabs by Kroppy.

When I first installed Tree Tabs, I just wanted vertical tabs. my favorite super-extension, TabMixPlus, had been obliterated by the Quantum change, but never did i care about trees, levels or groups. yeah, i saw these features touted on Tree Tabs, I DIDN'T CARE. i just knew I had tabs out my ears and couldn't deal with horror of horizontal tab display and navigation.

i tested out a bunch of vertical tab extensions but ultimately dug into Tree Tabs. Why?

THE COMPRESSED FORMAT OF PINNED TABS at the top of the Tree Tabs column. ingenious! once i saw it, I couldn't live without it.

the other bit of perfection was the compact height of the tabs. other extensions waste so much space with big tall tabs and huge fonts. this forces extra scrolling, but the real crime is allowing the user to view only 15 tabs at once! i also quickly embraced the ability to customize all the aesthetics, which only enhanced my joy at being reunited with functional tabs.

after 6 months of use, tabs quickly multiplying like rabbits on coke and viagra, i finally investigated Groups.

HEY, GROUPS ARE A GREAT IDEA! WHY DIDN'T I USE THEM BEFORE?!

while setting up my Groups, i also checked out Folders.

WHOA, GROUPS AND FOLDERS WORK *WONDERS* FOR ORGANIZATION WHEN YOU USE THEM TOGETHER!

what a sap i've been to ignore these useful features! with all this tab management brilliance in play, i hardly notice i have 300 tabs! think that's crazy? think of my tabs like an interactive task and research to-do list. much more productive than preposterous. i'm still not using trees (ironically), but i don't dare say "never!"

i recently trained myself to use the Tree Tab Settings and Re-open Tab buttons instead of right-clicks. also now taking advantage of unloading whole groups at once to save memory... been using these features for about a month and everything's now second nature.

today I re-discovered the Export Session button and contemplating putting it to work. Firefox restores my sessions, but a fail-safe would might be helpful.

guess you could say i've really come around on Tree Tabs, an incredible utility, and I'm super grateful to Kroppy for creating it. come New Year's, when I evaluate my extensions and contribute to my most beloved... Kroppy, you're a sure thing. you're building a productivity powerhouse. thank you for your vision and efforts. hope plenty appreciate your talents.

my only feature suggestions would be

1) some way to backup prefs and color formatting, though i'm assuming it's time consuming, else i would've already found it.

2) the ability to customize the tabs context menu. i could shave off 9 or 10 entries

3) k, just saw my third wish has been pre-granted LOL... F1 to toggle Tree Tabs sidebar. UH-MAZING.

the extension is already 5-stars. these are just first-world whines.

the only bug i've found is that sometimes when trying to drag and drop a tab, no tabs will move. it only happens once in a while, and i haven't yet noticed a pattern or precursor. what happens is, i'll grab a tab as usual, but instead of just dragging normally, where i clearly see both the insertion drop line that appears between other tabs, and the dual lines that designate a drop into a folder, those lines won't appear. the tabs i'm dragging _over_ do change color as the pointer sweeps over them, but nothing happens when i let go (regardless of where i let go). the tab i tried to move remains unmoved, and the tab name oddly remains italicized unless i click on it again to "reset" it.. this lasts several minutes at least. i usually go on with other things and forget it until some time later when it's working again.

wondering if this has to do with uBlock or uMatrix since i see a different script blocker listed as Tree Tabs- incompatible. But since this glitch is intermittent, I can't say, and it's not enough for me to quit on Tree Tabs.

aside from that, it's perfect--a dream extension. BRAVO.

Just Awesome. Can't do without it.

It works much faster than Tree Style Tabs, nice.

An excellent extension, only the icons of some sites on the tabs are not displayed. And on the original tabs are displayed.

This is a great addon. I really like the way I can put tabs in groups and then subdivide them into folders, great idea - glad somebody thought of that, I sure didn't. Some things I would like to see would be the option of having trees expand automatically when selecting the parent tab, colors for the folders title/background and have undo close tab to place the tab back in the tree where it was when closed. Over all a great addon.

Finally! I have my old tree-style tabs back again after the Firefox upgrade debacle.

I was using "Tree Style Tab" and it worked really well, but I like to be able to recall my 100+ tabs from previous sessions. So started to use "Tab Session Manager". That just made everything go bad. The tab tree would be loaded in a complete and utter mess. Making it completely useless.

So, came across this add-on and never looked back. Can save a tab tree, go back to a previous session, export to a JSON file for munging in external scripts. Nice!

Happy to donate to the developer as its saving me bucket loads of time.

[Edit: To the developer - You're on to a winner here! Keep improving it, but remember why people wanted to use your add-on in the first place.]

Très pratique pour le trie des onglets

Best tree-style tabs plugin! Very well crafted.

I made a whole bunch of groups, and I wanted to save them for later (they were all open at that time) so I right-clicked the group tab and selected "Hibernate". They disappeared (good), but how do I get them back?? I searched all the reviews, looked at all of the pictures, and NONE of them explain how to get back "Hibernated" groups -- or an explanation of what "Hibernate" even means! Looks like I lost a whole bunch of pages and scared to use this further. Help please!

EDIT: Thank you for the response @kroppy, problem solved! Would be nice to have this in the description so slow users like me will know what to do :D

I was looking for the ability to sort my open tabs via a firefox add-on/extension. I found this. Sorting isn't listed as a feature, but Tree Tabs effectively allows this.
Two Steps: I search and put the matched tabs in a group.
This tool seems better than the ones that just offer sorting. Just started using it today.

There was a bug.
Version 1.7.6
1. When adding a new tab, the tab is added, but it is not displayed.
When restarted, it is added to the bottom of the group.
The occurrence condition is unknown.
There is no problem immediately after rebooting, but it will occur again after a while.
I am setting to add all tabs as child tabs.

2. When tab group was imported, the tab structure was broken.
Also, "Rearranging tabs and folders" does not end.
It was not possible to open it by clicking the tab, and when restarted the tab had disappeared.
After importing it back to v1.4, it worked.

!
Oh, there was such a place.
I will report it when I find a bug in the future.
Thank you for maintenance.

Tree Tabs is easy to use, simple, but really useful when you need to manage a lot of tabs.

You can organize tabs in a tree structure in the sidebar. Fold it or unfold it. Navigation of tabs has made simple.

Wow, this is VERY promising and I'm already using it full time. If the bugs get ironed out this could be one of the most popular extensions for firefox.

I've been using this for quite a few months, and the developer has added some very nice features during that time. Organisation of tabs is a breeze with this thing.

I can select tabs without loading them, put tabs into general organisational groups and trees under each other, close and move lots of tabs at once, and so on. The tabs are also displayed pretty compactly by default, and additional information (such as whether or not a tab is loaded) is well conveyed. A number of these features cannot be found in some of the more well known tree-like tab extensions, which is why I use this one.

Would it be possible by an option to change this shortcut key ? *Ctrl+F2 to toggle Tree Tabs sidebar*
I would love to use Ctrl + Q, if possible, in a future upgrade consider for this option :)
Thank you very much, this extension is wonderful!