tabsidebar от zncoder

This simple addon list tabs vertically in the sidebar. It also includes a few common tab operations in the sidebar.

Add this to userChrome.css to remove the tab bar etc.

#main-window:not([extradragspace="true"]) #TabsToolbar > .toolbar-items {
opacity: 0;
pointer-events: none;
}
#main-window #TabsToolbar {
visibility: collapse !important;
}
#TabsToolbar[inFullscreen]{
display: none !important;
}
#sidebar-box #sidebar-header {
display: none !important;
}
#sidebar-box{
min-width: 54px !important;
max-width: 300px !important;
}