fenix-fox/chrome/minimal_text_fields.css

:root{
  --lwt-toolbar-field-background-color: transparent !important;
  --lwt-toolbar-field-border-color: transparent !important;
}

#search-box{
  -moz-appearance: none !important;
  background-color: var(--lwt-toolbar-field-background-color) !important;
  color: inherit !important;
}

#urlbar,
.searchbar-textbox{
  box-shadow: none !important;
}

#urlbar > *,
.searchbar-textbox > *{
  opacity: 0;
  transition: opacity 150ms linear
}

#urlbar > .urlbar-input-box,
.searchbar-textbox > moz-input-box{ opacity: 0.6 }

#identity-box,
#urlbar > *:hover,
#urlbar:focus-within > *,
.searchbar-textbox:hover > *,
.searchbar-textbox:focus-within > *{ opacity: 1 }

/* Information colors for identity-box in hidden state */

#identity-box{ border: none !important }
#urlbar:not(:hover) > #identity-box{ background-image: radial-gradient(closest-side circle at 16px, orange 10%,transparent 35% ); }
#urlbar:not(:hover) > #identity-box.verifiedIdentity{ background-image: radial-gradient(closest-side circle at 16px, lime 10%,transparent 35% ); }
#urlbar:not(:hover) > #identity-box > *{ opacity: 0 }

:root[title="Firefox Nightly"] #identity-box,
:root[title="Mozilla Firefox"] #identity-box,
#identity-box:hover,
#identity-box.chromeUI,
#identity-box.verifiedDomain{
  background-image: none !important;
}

#identity-box > #identity-icon-labels{ transition: max-width 150ms linear !important; }
#identity-box:not(:hover) > #identity-icon-labels{ max-width: 0px !important; }