diff --git a/tests/wpt/mozilla/meta/MANIFEST.json b/tests/wpt/mozilla/meta/MANIFEST.json
index ec0f751f6b0..9c27cb7cabf 100644
--- a/tests/wpt/mozilla/meta/MANIFEST.json
+++ b/tests/wpt/mozilla/meta/MANIFEST.json
@@ -968,6 +968,18 @@
           "url": "/_mozilla/css/setpropertypriority.html"
         }
       ],
+      "css/stacking_context_rtl.html": [
+        {
+          "path": "css/stacking_context_rtl.html",
+          "references": [
+            [
+              "/_mozilla/css/stacking_context_rtl-ref.html",
+              "=="
+            ]
+          ],
+          "url": "/_mozilla/css/stacking_context_rtl.html"
+        }
+      ],
       "css/word-spacing.html": [
         {
           "path": "css/word-spacing.html",
@@ -1142,4 +1154,4 @@
   "rev": null,
   "url_base": "/_mozilla/",
   "version": 2
-}
+}
\ No newline at end of file