yo! I second "Can't live without it"
Thanks a LOT for this awesome extension.
Several years ago (about 6 i think), the sudden inspiration crossed my mind, that tabs should not be listed horizontally, and after some longer research at that point in time (treestyletab was lesser known), i found this and was happy EVER AFTER.
It's pretty incredible that the devs made this working with firefox Quantum out of the box, I can't believe the effort.
I just wanna say: Thank you!
And you don't even want Donations, tears in my eyes, much love :)

I like it a lot, but I'd like to be able to change the background and text colors and weights of the tabs themselves in Firefox 57/linux. Some of the .css tweaks work, some work in strange ways, and some don't work at all. It was way better before FF57.

TST is the reason I've never even considered switching to using another browser. Works perfectly on FF57. Thank you so much for all your hard work!

Thanks for this add on, it's realy helpfully for user who use a lot of tabs in a session.

I really miss 2 things that wass very usefull, the auto hide, and the transparency without rezize the webpage area.

I don't know if it's posible cus the api limits.

Thank you for this very useful addon, cannot use browser without it.

Splendid job on converting to Firefox Quantum. With the changes to chrome.css from the wiki, it looks great!

Так изуродовать прекрасное дополнение ... Это надо было приложить массу усилий.

ok

Nope. This will not work until the horizontal tabs can be eliminated. It is way too odd to have two tabs areas showing.

Tree-style tabs are more compact and orderly than organizing tabs through the normal tabs bar. This extension has a few bugs in it, but it's still indispensable to saving time on the internet! Thank you, Piro. :)

Perfect when opening lots of tabs on a widescreen monitor. All tabs remain readable contrary to the normal tab layout.

Io non voglio vedere le schede in alto. Spero che questo problema sia risolto in futuro.

if not this plug-in I'd give up using FF and go for Chrome!

This is must have extension. It would be even greater if it could work in tandem with ColorfulTabs.

Just to remind older comments. One can hide FireFox tab bar and Side Panel title with userChrome.css file like that:

@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul");

/* to hide the native tabs */
#TabsToolbar { visibility: collapse; }

/* to hide the sidebar header */
#sidebar-header { visibility: collapse; }

The best vertical tabs solution. I cannot use Firefox without it.

After Firefox killed TabMixPlus I thought I would have to switch to another browser. Eventually I found Tree Style Tab, which is even better. Now I just wish I had a way to turn off Firefox's own tabs, since they are so lacking in features as to be almost useless.