diff --git a/tests/ref/basic.list b/tests/ref/basic.list
index 952afe64969..8972eb7f7e3 100644
--- a/tests/ref/basic.list
+++ b/tests/ref/basic.list
@@ -246,7 +246,6 @@ resolution=300x300,device-pixel-ratio=2 != pixel_snapping_position_a.html pixel_
== png_rgba_colorspace_a.html png_rgba_colorspace_b.html
== position_abs_cb_with_non_cb_kid_a.html position_abs_cb_with_non_cb_kid_b.html
== position_abs_height_width_a.html position_abs_height_width_b.html
-== position_abs_margin_top_percentage_a.html position_abs_margin_top_percentage_b.html
# commented out because multiple layers don't work with reftests --pcwalton
# == position_fixed_a.html position_fixed_b.html
# == position_fixed_simple_a.html position_fixed_simple_b.html
diff --git a/tests/wpt/mozilla/meta/MANIFEST.json b/tests/wpt/mozilla/meta/MANIFEST.json
index 29536dc2822..7f88ab39c1e 100644
--- a/tests/wpt/mozilla/meta/MANIFEST.json
+++ b/tests/wpt/mozilla/meta/MANIFEST.json
@@ -695,6 +695,18 @@
"url": "/_mozilla/css/position_abs_left_a.html"
}
],
+ "css/position_abs_margin_top_percentage_a.html": [
+ {
+ "path": "css/position_abs_margin_top_percentage_a.html",
+ "references": [
+ [
+ "/_mozilla/css/position_abs_margin_top_percentage_b.html",
+ "=="
+ ]
+ ],
+ "url": "/_mozilla/css/position_abs_margin_top_percentage_a.html"
+ }
+ ],
"css/position_abs_nested_a.html": [
{
"path": "css/position_abs_nested_a.html",
@@ -3240,6 +3252,18 @@
"url": "/_mozilla/css/position_abs_left_a.html"
}
],
+ "css/position_abs_margin_top_percentage_a.html": [
+ {
+ "path": "css/position_abs_margin_top_percentage_a.html",
+ "references": [
+ [
+ "/_mozilla/css/position_abs_margin_top_percentage_b.html",
+ "=="
+ ]
+ ],
+ "url": "/_mozilla/css/position_abs_margin_top_percentage_a.html"
+ }
+ ],
"css/position_abs_nested_a.html": [
{
"path": "css/position_abs_nested_a.html",
diff --git a/tests/ref/position_abs_margin_top_percentage_a.html b/tests/wpt/mozilla/tests/css/position_abs_margin_top_percentage_a.html
similarity index 85%
rename from tests/ref/position_abs_margin_top_percentage_a.html
rename to tests/wpt/mozilla/tests/css/position_abs_margin_top_percentage_a.html
index 0abb60c37b7..790e8afac62 100644
--- a/tests/ref/position_abs_margin_top_percentage_a.html
+++ b/tests/wpt/mozilla/tests/css/position_abs_margin_top_percentage_a.html
@@ -1,5 +1,6 @@
+