ശ്യാം കുമാർ 
When unhiding the vertical tab bar, it expands to show titles; I don't want that. So…
#sidebar-main { max-width: 50px !important }
#tabbrowser-tabs[orient="vertical"]
{
.tab-text.tab-label { display: none !important }
#tabs-newtab-button { max-width: 0px !important; position:absolute; right:4px }
.tabbrowser-tab {.tab-close-button { position: absolute; left: -4px; top: -4px } }
}