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

tab.tabbrowser-tab[faviconized="true"][treestyletab-subtree-collapsed="true"] { min-width: 70px !important; max-width: 70px !important }
tab.tabbrowser-tab[faviconized="true"][treestyletab-children]:not([treestyletab-subtree-collapsed="true"]) { min-width: 52px !important; max-width: 52px !important }