I used TreeStyleTab for a while but it never quite felt "right" and all the tweaks to get rid of the top tab bar are such a pain. It almost seems like too much with all the nested tabs (I know you can turn these off)
I hate to say it but the best vertical tab implementation I've seen is in Edge. Easily toggle-able between horizontal/vertical tabs, there's a way to collapse it to just favicons, you can use collections to group tabs together (like in Chrome). It's honestly one of the features that keeps me coming back to Edge, privacy be damned.
I think the only feature I really miss from Firefox is container tabs.
$ cat userChrome.css
/* Hide horizontal tabs at the top of the window */
#main-window[tabsintitlebar="true"]:not([extradragspace="true"]) #TabsToolbar > .toolbar-items {
opacity: 0;
pointer-events: none;
}
#main-window:not([tabsintitlebar="true"]) #TabsToolbar {
visibility: collapse !important;
}
/* Hide the "Tree Style Tab" header at the top of the sidebar */
#sidebar-box[sidebarcommand="treestyletab_piro_sakura_ne_jp-sidebar-action"] #sidebar-header {
display: none;
}
I hate to say it but the best vertical tab implementation I've seen is in Edge. Easily toggle-able between horizontal/vertical tabs, there's a way to collapse it to just favicons, you can use collections to group tabs together (like in Chrome). It's honestly one of the features that keeps me coming back to Edge, privacy be damned.
I think the only feature I really miss from Firefox is container tabs.