--- a/devtools/client/shared/components/notification-box.css
+++ b/devtools/client/shared/components/notification-box.css
@@ -20,18 +20,18 @@
 .notificationbox .notification-button {
   text-align: right;
 }
 
 .notificationbox .messageText {
   flex-grow: 1;
 }
 
-.notificationbox .details:-moz-dir(rtl)
-.notificationbox .notificationInner:-moz-dir(rtl) {
+.notificationbox .details:dir(rtl)
+.notificationbox .notificationInner:dir(rtl) {
   flex-direction: row-reverse;
 }
 
 /* Style */
 
 .notificationbox .notification {
   background-color: InfoBackground;
   text-shadow: none;