ShadowFox/userChrome-files/windows_fixes/library.css

@-moz-document url(chrome://browser/content/places/places.xul),
url(chrome://browser/content/places/bookmarkProperties.xul) {

  #metaTagsCaption,
  #security-identity,
  #security-privacy,
  #security-technical,
  #security-identity-groupbox,
  #security-privacy-groupbox,
  #security-technical-groupbox {
    -moz-appearance: none !important;
    background-color: var(--primary-dark-color) !important;
    border: none !important;
    color: var(--grey-10) !important;
  }

  #security-identity-groupbox,
  #security-privacy-groupbox,
  #security-technical-groupbox {
    -moz-appearance: none !important;
    background-color: var(--dark-accent) !important;
  }

}