Tabcenter redux - hide tab bar & autoshrink sidebar

userChrome.css

/*
 * This hides the horizontal top-level tab strip & makes the tab sidebar autoshrink.
 *
 * This needs to be added to the userChrome.css, see e.g. here for more:
 * https://github.com/eoger/tabcenter-redux/wiki/Custom-CSS-Tweaks#userchromecss-tweaks
 *
 * Also requires in about:config to set browser.tabs.drawInTitlebar to false.
 */

@-moz-document url("chrome://browser/content/browser.xul") {
  #TabsToolbar {
    height: 22px;
    visibility: collapse !important;
  }

  #tabbrowser-tabs {
    visibility: collapse;
  }
}

#tabbrowser-tabs {
  visibility: collapse !important;
}

#sidebar-box {
  overflow-x: hidden;
  min-width: 50px !important;
  max-width: 50px !important;
  transition: all 0.25s ease !important;
}

#sidebar-box:hover {
  min-width: 250px !important;
  max-width: 250px !important;
}