--- a/layout/style/res/ua.css
+++ b/layout/style/res/ua.css
@@ -400,18 +400,17 @@ div:-moz-native-anonymous.moz-accessible
   /* Add transition effect to make caret size changing smoother. */
   transition-duration: 250ms;
   transition-property: width, height, margin-left;
 
   position: absolute;
   z-index: 2147483647;
 }
 
-div:-moz-native-anonymous.moz-accessiblecaret > #text-overlay,
-div:-moz-native-anonymous.moz-accessiblecaret > #image {
+div:-moz-native-anonymous.moz-accessiblecaret > :is(#text-overlay, #image) {
   width: 100%;
 
   /* Override this property in moz-custom-content-container to make dummy touch
    * listener work. */
   pointer-events: auto;
 }
 
 div:-moz-native-anonymous.moz-accessiblecaret > #image {
@@ -420,27 +419,25 @@ div:-moz-native-anonymous.moz-accessible
   background-repeat: no-repeat;
   background-origin: content-box;
 }
 
 div:-moz-native-anonymous.moz-accessiblecaret.normal > #image {
   background-image: url("resource://gre-resources/accessiblecaret-normal@1x.png");
 }
 
-div:-moz-native-anonymous.moz-accessiblecaret.left > #text-overlay,
-div:-moz-native-anonymous.moz-accessiblecaret.left > #image {
+div:-moz-native-anonymous.moz-accessiblecaret.left > :is(#text-overlay, #image) {
   margin-left: -39%;
 }
 
 div:-moz-native-anonymous.moz-accessiblecaret.left > #image {
   background-image: url("resource://gre-resources/accessiblecaret-tilt-left@1x.png");
 }
 
-div:-moz-native-anonymous.moz-accessiblecaret.right > #text-overlay,
-div:-moz-native-anonymous.moz-accessiblecaret.right > #image {
+div:-moz-native-anonymous.moz-accessiblecaret.right > :is(#text-overlay, #image) {
   margin-left: 41%;
 }
 
 div:-moz-native-anonymous.moz-accessiblecaret.right > #image {
   background-image: url("resource://gre-resources/accessiblecaret-tilt-right@1x.png");
 }
 
 div:-moz-native-anonymous.moz-accessiblecaret.none {
@@ -485,43 +482,40 @@ div:-moz-native-anonymous.moz-accessible
   }
 
   div:-moz-native-anonymous.moz-accessiblecaret.right > #image {
     background-image: url("resource://gre-resources/accessiblecaret-tilt-right@2.25x.png");
   }
 }
 
 %ifdef ANDROID
-div:-moz-native-anonymous.moz-accessiblecaret > #text-overlay,
-div:-moz-native-anonymous.moz-accessiblecaret > #image {
+div:-moz-native-anonymous.moz-accessiblecaret > :is(#text-overlay, #image) {
   /* border: 0.1px solid red; */ /* Uncomment border to see the touch target. */
   padding-left: 59%; /* Enlarge the touch area. ((48-22)/2)px / 22px ~= 59% */
   padding-right: 59%; /* Enlarge the touch area. */
   margin-left: -59%;
 }
 
 div:-moz-native-anonymous.moz-accessiblecaret > #image {
   padding-bottom: 59%; /* Enlarge the touch area. */
 }
 
 div:-moz-native-anonymous.moz-accessiblecaret.normal > #image {
   background-image: url("chrome://geckoview/skin/images/accessiblecaret-normal-hdpi.png");
 }
 
-div:-moz-native-anonymous.moz-accessiblecaret.left > #text-overlay,
-div:-moz-native-anonymous.moz-accessiblecaret.left > #image {
+div:-moz-native-anonymous.moz-accessiblecaret.left > :is(#text-overlay, #image) {
   margin-left: -109%;
 }
 
 div:-moz-native-anonymous.moz-accessiblecaret.left > #image {
   background-image: url("chrome://geckoview/skin/images/accessiblecaret-tilt-left-hdpi.png");
 }
 
-div:-moz-native-anonymous.moz-accessiblecaret.right > #text-overlay,
-div:-moz-native-anonymous.moz-accessiblecaret.right > #image {
+div:-moz-native-anonymous.moz-accessiblecaret.right > :is(#text-overlay, #image) {
   margin-left: -12%;
 }
 
 div:-moz-native-anonymous.moz-accessiblecaret.right > #image {
   background-image: url("chrome://geckoview/skin/images/accessiblecaret-tilt-right-hdpi.png");
 }
 
 @media (min-resolution: 1.5dppx) {