diff --git a/tests/ref/basic.list b/tests/ref/basic.list
index a9319ef1c0a..444a7d8a9cf 100644
--- a/tests/ref/basic.list
+++ b/tests/ref/basic.list
@@ -12,7 +12,6 @@ fragment=top != ../html/acid2.html acid2_ref.html
== acid1_a.html acid1_b.html
== acid2_noscroll.html acid2_ref_broken.html
flaky_cpu == append_style_a.html append_style_b.html
-== background_size_zero_a.html background_size_zero_ref.html
== background_style_attr.html background_ref.html
== basic_width_px.html basic_width_em.html
== block_formatting_context_a.html block_formatting_context_ref.html
diff --git a/tests/wpt/mozilla/meta/MANIFEST.json b/tests/wpt/mozilla/meta/MANIFEST.json
index 6bca49aebc0..69a7167f620 100644
--- a/tests/wpt/mozilla/meta/MANIFEST.json
+++ b/tests/wpt/mozilla/meta/MANIFEST.json
@@ -399,6 +399,18 @@
"url": "/_mozilla/css/background_size_shorthand_a.html"
}
],
+ "css/background_size_zero_a.html": [
+ {
+ "path": "css/background_size_zero_a.html",
+ "references": [
+ [
+ "/_mozilla/css/background_size_zero_ref.html",
+ "=="
+ ]
+ ],
+ "url": "/_mozilla/css/background_size_zero_a.html"
+ }
+ ],
"css/class-namespaces.html": [
{
"path": "css/class-namespaces.html",
@@ -1580,6 +1592,18 @@
"url": "/_mozilla/css/background_size_shorthand_a.html"
}
],
+ "css/background_size_zero_a.html": [
+ {
+ "path": "css/background_size_zero_a.html",
+ "references": [
+ [
+ "/_mozilla/css/background_size_zero_ref.html",
+ "=="
+ ]
+ ],
+ "url": "/_mozilla/css/background_size_zero_a.html"
+ }
+ ],
"css/class-namespaces.html": [
{
"path": "css/class-namespaces.html",
diff --git a/tests/ref/background_size_zero_a.html b/tests/wpt/mozilla/tests/css/background_size_zero_a.html
similarity index 71%
rename from tests/ref/background_size_zero_a.html
rename to tests/wpt/mozilla/tests/css/background_size_zero_a.html
index c059881513b..64b7431f74e 100644
--- a/tests/ref/background_size_zero_a.html
+++ b/tests/wpt/mozilla/tests/css/background_size_zero_a.html
@@ -1,4 +1,5 @@
+