This might be a really weird comment, but I really wonder why there is no copy of this extension on Chrome?

This add-on has become very useful now that I do all my work from home. Everything works well and is easy to customize.

One of the best extension I use! Using a normal browser become a pain without it. Thank to Piro for making it (and for the hard work involved in porting it to webextension)

Great extension

Tree Style Tab has noticably increased my efficiency using Firefox. I tried using Vivaldi's with its vertical tabs - that's pretty good, but I find Tree Style Tab to be more polished. I can keep many tabs and thoughts ongoing, yet easily shift topics by hopping from one subtree to another. Recommended.

easily the best solution for treed tabs in any browser. it's got some buggy habits but still leaps and bounds better than any solution i've found on firefox or other browsers. i've been using it for several years now and my workflow depends on it.

@Ons-joe, try any of the following CSS codes:

/* Hide Tab Bar contents (Doesn't remove title bar)
#TabsToolbar .tabbrowser-tab,
#TabsToolbar .tabs-newtab-button,
#new-tab-button, #alltabs-button {
display: none !important;
} */

/* Hide Tab Bar contents (Removes title bar) */
#titlebar {
visibility: collapse !important;
}

/* The margin-top so that the buttons and search bars on the nav bar aren't cut-off when Firefox is maximized */
#main-window[sizemode="maximized"] #nav-bar {
margin-top: 8px;
}

/* To hide the sidebar header */
#sidebar-header {
display: none !important;
}

Tree-style tabs is life-changing if you do any kind of work that involves having a lot of tabs open at once. Having them easily grouped by project/subject/whatever you want makes going back to traditional tabs feel like such a mess! I've been a happy user of this extension for years.