diff --git a/res/css/views/messages/_MKeyVerificationRequest.scss b/res/css/views/messages/_MKeyVerificationRequest.scss
index b4cde4e7ef..87a75dee82 100644
--- a/res/css/views/messages/_MKeyVerificationRequest.scss
+++ b/res/css/views/messages/_MKeyVerificationRequest.scss
@@ -25,7 +25,7 @@ limitations under the License.
         width: 12px;
         height: 16px;
         content: "";
-        mask: url("$(res)/img/e2e/normal.svg");
+        mask-image: url("$(res)/img/e2e/normal.svg");
         mask-repeat: no-repeat;
         mask-size: 100%;
         margin-top: 4px;
@@ -33,7 +33,7 @@ limitations under the License.
     }
 
     &.mx_KeyVerification_icon_verified::after {
-        mask: url("$(res)/img/e2e/verified.svg");
+        mask-image: url("$(res)/img/e2e/verified.svg");
         background-color: $accent-color;
     }