diff --git a/tests/wpt/mozilla/tests/css/inline_stacking_context.html b/tests/wpt/mozilla/tests/css/inline_stacking_context.html
index 24de45e229e..255190a820c 100644
--- a/tests/wpt/mozilla/tests/css/inline_stacking_context.html
+++ b/tests/wpt/mozilla/tests/css/inline_stacking_context.html
@@ -10,5 +10,9 @@
             <span style="color: transparent;"><img src="100x100_green.png"></span>
             <img style="filter: blur(0px);" src="100x100_green.png">
         </div>
+        <div style="font-size: 25px">
+            <span style="transform:scale(1)">X</span>
+            <span style="transform:scale(1)">O</span>
+        </div>
     </body>
 </html>
diff --git a/tests/wpt/mozilla/tests/css/inline_stacking_context_ref.html b/tests/wpt/mozilla/tests/css/inline_stacking_context_ref.html
index 11c78d4a409..8e9fe61a071 100644
--- a/tests/wpt/mozilla/tests/css/inline_stacking_context_ref.html
+++ b/tests/wpt/mozilla/tests/css/inline_stacking_context_ref.html
@@ -8,5 +8,9 @@
             <span style="color: transparent;"><img src="100x100_green.png"></span>
             <img src="100x100_green.png">
         </div>
+        <div style="font-size: 25px">
+            <span>X</span>
+            <span>O</span>
+        </div>
     </body>
 </html>