diff --git a/tests/wpt/mozilla/tests/css/2x4.png b/tests/wpt/mozilla/tests/css/2x4.png new file mode 100644 index 00000000000..7efc762459b Binary files /dev/null and b/tests/wpt/mozilla/tests/css/2x4.png differ diff --git a/tests/wpt/mozilla/tests/css/4x2.png b/tests/wpt/mozilla/tests/css/4x2.png new file mode 100644 index 00000000000..eb0c5cda971 Binary files /dev/null and b/tests/wpt/mozilla/tests/css/4x2.png differ diff --git a/tests/ref/background_size.png b/tests/wpt/mozilla/tests/css/background_size.png similarity index 100% rename from tests/ref/background_size.png rename to tests/wpt/mozilla/tests/css/background_size.png