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!

Been using Tree Style Tabs for years but found this and decided to give it a whirl. After three days, decided to clean up a mess of tabs. Selected one tab to keep, clicked "Close other tabs," and sure enough ALL other tabs closed. Unfortunately that included ALL my pinned tabs!! MAJOR oversight!!! Uninstalled. I'll stick with Tree Style Tabs. I find it far better designed and better thought out.

Edit for added detail: A few other reasons I've ditched this in favor of TST:

Messed up the order of pinned tabs
Doesn't have a decent way to organized tab groups automatically with good settings
Appearance settings are way to convoluted. Users shouldn't have to be web designers to understand what to do with appearance settings. There ought to be a few graphical examples of choices. Keep it simple stupid. Simplicity is always better.
Honestly, I find the appearance in terms of usability far to cluttered.

In short, IMHO, Tree Style Tabs is so far ahead of this extension in terms of feel, look and usability right out of the box this one just isn't worth the time. Yet...

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.

Now that Tab Mix Plus is defunct, I needed something to allow me to easily navigate a lot of tabs. Not sure if this is it.

The basic functionality is sound, but who wants to manually create groups of tabs?

Clearly needs tools for automatic grouping. Most obviously, group by site. Group by date would be pretty handy too (and of course group by date then site, and group by site then date).

Ainda contém bugs quando se usam muitas abas abertas

I TOTALLY LIKE THE IDEA. For a tab messie like me, grouping tabs in categories and folders is just a dream coming true.

Adding in the "unload tab" feature is really, really giving me wet pants :-)

However, the multitude of bugs and drawbacks do spoil the fun quite a bit.

Most importantly, this extension does - to the best of my knowledge - not work properly with ANY session saver. There IS a built-in session saver in Tree Tabs but that is cumbersome to use AND has bugs! So, for example if you restore your session saved with the Tree-Tabs built-in session saver, all tab groups will be restored - EMPTY. The tabs that were in them ALL go to the "ungrouped" tab, so you have to manually put them back where they were. That sort of makes the whole concept of a specialized buit-in solution a bit volatile.

Another pretty unnerving bug is that closing the bottom tab (or tree) in a group always switches you into another group.

So, thank you for taking on the tab management with this new, very innovative approach but PLEASE try to improve on it a little more.

Just Awesome. Can't do without it.

Override drag&drop Firefox functions.

It works much faster than Tree Style Tabs, nice.

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

I've been using this only for a few days as a possible replacement for "Tree Style Tabs" (which loads slow). I like it and it reminds me of the the old Tab Tree extension with new abilities. I like the groups idea. But I guess I'm a bit confused as to why both groups and folders, since they perform the same function (from what I've seen), except one is vertical and the other horizontal.

I'm giving it three stars for two reasons (and would happily update if these issues were addressed):
1. Ctrl-W (close tab) not only closes the tab, but jumps you to the last group in the list. It should close the tab and not only remain in the same group, but go to the previous tab.
2. There is no way to contact the developer from the Options screen (only links to donate).

[UPDATE 1] Tabs load instantly, which is awesome. Ctrl-W *does* close a tab and return to the previous or next-up tab ((+1 star)). Groups are awesome, esp since I can keep an eye on the number of tabs! Tab unloading is great, but I wish the pinned tabs wouldn't unload. But the reload time isn't too painful. Still no way to contact author from the Options screen.

[UPDATE 2] Groups all of a sudden disappeared upon browser update and restart. Tabs are still there, but now they are all in the Ungrouped default group. Browser updated to 62.0.2.

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

5 stars because it does its job well and there is a lot of features available.
Minus 1 star because in terms of default (I say default because you can customize the theme) ergonomics, it could be better.