diff --git a/tests/ref/basic.list b/tests/ref/basic.list
index 78086e2b0d1..f0cfd3c2f42 100644
--- a/tests/ref/basic.list
+++ b/tests/ref/basic.list
@@ -13,8 +13,6 @@ fragment=top != ../html/acid2.html acid2_ref.html
flaky_cpu == append_style_a.html append_style_b.html
# `?` and `#` in the name is a test for https://github.com/servo/servo/issues/3340
-== iframe/stacking_context_position_a.html iframe/stacking_context_position_ref.html
-
# inline_border_a.html inline_border_b.html
flaky_cpu == linebreak_simple_a.html linebreak_simple_b.html
# Fails intermittently (#3636)
diff --git a/tests/wpt/mozilla/meta/MANIFEST.json b/tests/wpt/mozilla/meta/MANIFEST.json
index 70e04716a3a..8a152e381bb 100644
--- a/tests/wpt/mozilla/meta/MANIFEST.json
+++ b/tests/wpt/mozilla/meta/MANIFEST.json
@@ -1795,6 +1795,18 @@
"url": "/_mozilla/css/iframe/stacking_context.html"
}
],
+ "css/iframe/stacking_context_position_a.html": [
+ {
+ "path": "css/iframe/stacking_context_position_a.html",
+ "references": [
+ [
+ "/_mozilla/css/iframe/stacking_context_position_ref.html",
+ "=="
+ ]
+ ],
+ "url": "/_mozilla/css/iframe/stacking_context_position_a.html"
+ }
+ ],
"css/image_rendering_auto_a.html": [
{
"path": "css/image_rendering_auto_a.html",
@@ -7470,6 +7482,18 @@
"url": "/_mozilla/css/iframe/stacking_context.html"
}
],
+ "css/iframe/stacking_context_position_a.html": [
+ {
+ "path": "css/iframe/stacking_context_position_a.html",
+ "references": [
+ [
+ "/_mozilla/css/iframe/stacking_context_position_ref.html",
+ "=="
+ ]
+ ],
+ "url": "/_mozilla/css/iframe/stacking_context_position_a.html"
+ }
+ ],
"css/image_rendering_auto_a.html": [
{
"path": "css/image_rendering_auto_a.html",
diff --git a/tests/ref/iframe/stacking_context_position_a.html b/tests/wpt/mozilla/tests/css/iframe/stacking_context_position_a.html
similarity index 77%
rename from tests/ref/iframe/stacking_context_position_a.html
rename to tests/wpt/mozilla/tests/css/iframe/stacking_context_position_a.html
index be4b870407f..262e573e4a8 100644
--- a/tests/ref/iframe/stacking_context_position_a.html
+++ b/tests/wpt/mozilla/tests/css/iframe/stacking_context_position_a.html
@@ -1,3 +1,4 @@
+
diff --git a/tests/ref/iframe/stacking_context_position_ref.html b/tests/wpt/mozilla/tests/css/iframe/stacking_context_position_ref.html
similarity index 100%
rename from tests/ref/iframe/stacking_context_position_ref.html
rename to tests/wpt/mozilla/tests/css/iframe/stacking_context_position_ref.html