treestyletab/content/treestyletab/treestyletab.css

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

tab .treestyletab-twisty,
tab .treestyletab-counter-container,
tab .treestyletab-drop-marker,
tab[treestyletab-children]:not([treestyletab-subtree-collapsed="true"]) .treestyletab-counter-container {
	display: none;
}

tab[treestyletab-children] .treestyletab-twisty,
tab[treestyletab-children] .treestyletab-counter-container,
tab[treestyletab-drop-position] .treestyletab-drop-marker {
	display: -moz-box;
}

tab[treestyletab-collapsed="true"] {
	visibility: collapse;
}

tabbrowser[treestyletab-vertical="true"] .tabbrowser-arrowscrollbox > .scrollbutton-up,
tabbrowser[treestyletab-vertical="true"] .tabbrowser-arrowscrollbox > .scrollbutton-down-stack,
tabbrowser[treestyletab-vertical="true"] .tabs-alltabs-stack,
tabbrowser[treestyletab-vertical="true"] .tabs-closebutton-box {
	display: none !important;
}

tabbrowser[treestyletab-vertical="true"] > tabbox {
	-moz-box-orient: horizontal !important;
}