Well, it's the best work around so far until a true tab-grouping add-on is developed for FF 57. It's the whole reason I use FF. Wish you could label the parent tabs something else than the parent website. For example, "Everyday Stuff" or "Suppliers." We have several suppliers and different types of suppliers so it would be nice to label each Tree like the tab groups of 56.

The previous version had exactly what I was searching for, meaning the ability to group (and collapse) tabs together while remaining at the top like the default tabs.

I am using half-width windows all the time, so the side bars take way too much space for me, so sadly I had to disable it once firefox forced its update and new plugin versions on me, but I am still hopeful that one day it will give us that functionnality back.

My favorite plugin by far! Always updated even for Firefox 57.

удобно

Update : there is a companion extension that supports scrolling among the tabs using the wheel of the mouse: https://addons.mozilla.org/en-US/firefox/addon/tree-style-tab-mouse-wheel/
Therefore the Autohotkey solution is now obsolete.
------------------------- old review -----------------------------
One more 5 Stars and a bigup for Piro!

I really like to be able to scroll the tabs in my Firefox. Since v57, it's not possible anymore, so here is a solution found on the"Tab Wheel Scroll" extension page :

1) Get Autohotkey
2) Create the following script:


#IfWinActive ahk_class MozillaWindowClass
;MouseGetPos, [OutputVarX, OutputVarY, OutputVarWin, OutputVarControl, 1|2|3]
~WheelDown::
MouseGetPos X, Y
if ( X < 205 )
SendInput ^{PgDn}
Return
~WheelUp::
MouseGetPos X, Y
if ( X < 205 )
SendInput ^{PgUp}
Return

And run the script whenever you launch Firefox.
You must adjust the X value ("205" pixels in my case) to the width of your vertical tab.

Great extension that allow me to easily manage 100+ tab

the main reason I Insist on using firefox.おつかれさまです

Very good and Tab Search will make it better.

This extension is great for me who keep open many tabs and it helps me keep being productive by organizing hierarchically my browsing, I cannot do without anymore, no equivalent for chrome. The new version integrate well in the new Firefox (57), but it's less useful with the top bar staying still and the title. I solved it with userChrome.css, but it's would be easier with an option for the non-technical user. Great work and thanks a lot !

This extension would be perfect if the author could hide the children tabs from the top bar tab so you would have only the parents on the top and the children on the left, a superlative UX tweaks!

It's working well.

Very good and useful.

I'm very glad Piro had a revised version of Tree Style Tab for the latest major revision of Firefox. The user interface has changed, and functionality is somewhat less, but the core features remain present.

Anonymous user 097179 ty for great explanation!!! Now all works right for this great extension!

Been using this addon for years now, and tried a few alternatives, but nothing ever came close.
The developer Piroor is also very active on his GitHub.

I use this as a replacement for grouped tabs in Firefox 57. Actually it's better than grouped tabs since you can't have nested groups. With this Add-on you can.
But the Add-on really needs an option to NOT open new tabs as a child tab when I middle click on a link. Opening a link from a website often but not always says something about the hierarchical relationship between those tabs. When I click on a link in a list of search results that makes sense. When I click on a "see also ..." link at the bottom of the page of some documentation or on a link to related videos on YouTube it's just nasty that those new tabs always become child tabs of the current one.

Not Piro's fault for the top tabs, that is Firefox's new API limitation and Piro has gone to great lengths to get it this far. Just a simple couple of steps to get rid of the top tool bar if you read the bubble information in the new update or just look for the links in these reviews.

Still an indispensable addon for Firefox. I like the new version and thrilled it made it over to the new version 57. I wouldn't use Firefox without it to be quite honest.

Thank you Piro, been using your addons for years. My workflow would not be the same without them.

For those that can't be bothered to educate themselves, here's a copy/paste from someone that took the time to write out step by step instructions. Takes less than 2 minutes to do.

If you're like me and primarily used this add-on to remove the tabs from the top, follow these instructions provided by user Soulyaris:

"Inside your profile folder(it usual c:\Users\*user*\AppData\Roaming\Mozilla\Firefox\Profiles\*something*-default (check date of modified),
Create a new folder named chrome.
Inside the chrome folder, create two new files, userChrome.css and userContent.css.
At the top of userChrome.css, add (copy/paste) the following:

@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul");
/* Hides tab bar*/
#TabsToolbar { visibility: collapse; }

Save it and restart firefox. Enjoy."

That's it, enjoy tree-style without the top tabs.

It updated on it's own and I DO NOT LIKE the new version. Why the hell would I still want the top taps if I have side tabs. As far as I can tellthere's no way to fix this, which pretty much renders is useless to me.