--- a/browser/themes/shared/urlbar-searchbar.inc.css
+++ b/browser/themes/shared/urlbar-searchbar.inc.css
@@ -34,24 +34,24 @@
 }
 
 #urlbar:hover,
 .searchbar-textbox:hover {
   border-color: hsla(240,5%,5%,.35);
   box-shadow: 0 1px 6px rgba(0,0,0,.1);
 }
 
-#urlbar:-moz-lwtheme,
+#urlbar:not([readonly]):-moz-lwtheme,
 #navigator-toolbox .searchbar-textbox:-moz-lwtheme {
   background-color: var(--url-and-searchbar-background-color, hsla(0,0%,100%,.8));
   color: var(--url-and-searchbar-color, black);
 }
 
-#urlbar:-moz-lwtheme:hover,
-#urlbar:-moz-lwtheme[focused="true"],
+#urlbar:not([readonly]):-moz-lwtheme:hover,
+#urlbar:not([readonly]):-moz-lwtheme[focused="true"],
 #navigator-toolbox .searchbar-textbox:-moz-lwtheme:hover,
 #navigator-toolbox .searchbar-textbox:-moz-lwtheme[focused="true"] {
   background-color: var(--url-and-searchbar-background-color, white);
 }
 
 :root[uidensity=compact] #urlbar,
 :root[uidensity=compact] .searchbar-textbox {
   min-height: 26px;