diff --git a/tests/ref/basic.list b/tests/ref/basic.list
index ead25bc53d7..6f5a4fa1ceb 100644
--- a/tests/ref/basic.list
+++ b/tests/ref/basic.list
@@ -34,7 +34,6 @@ prefs:"layout.writing-mode.enabled" == iframe/size_attributes_vertical_writing_m
== iframe/stacking_context.html iframe/stacking_context_ref.html
== iframe/stacking_context_position_a.html iframe/stacking_context_position_ref.html
-!= inline_background_a.html inline_background_ref.html
== inline_block_margin_auto_a.html inline_block_margin_auto_ref.html
== inline_block_parent_width.html inline_block_parent_width_ref.html
== inline_block_parent_width_percentage.html inline_block_parent_width_ref.html
diff --git a/tests/wpt/mozilla/meta/MANIFEST.json b/tests/wpt/mozilla/meta/MANIFEST.json
index 340cbde980b..3d0faa83feb 100644
--- a/tests/wpt/mozilla/meta/MANIFEST.json
+++ b/tests/wpt/mozilla/meta/MANIFEST.json
@@ -1763,6 +1763,18 @@
"url": "/_mozilla/css/inline_absolute_out_of_flow_a.html"
}
],
+ "css/inline_background_a.html": [
+ {
+ "path": "css/inline_background_a.html",
+ "references": [
+ [
+ "/_mozilla/css/inline_background_ref.html",
+ "!="
+ ]
+ ],
+ "url": "/_mozilla/css/inline_background_a.html"
+ }
+ ],
"css/inline_block_baseline_a.html": [
{
"path": "css/inline_block_baseline_a.html",
@@ -6696,6 +6708,18 @@
"url": "/_mozilla/css/inline_absolute_out_of_flow_a.html"
}
],
+ "css/inline_background_a.html": [
+ {
+ "path": "css/inline_background_a.html",
+ "references": [
+ [
+ "/_mozilla/css/inline_background_ref.html",
+ "!="
+ ]
+ ],
+ "url": "/_mozilla/css/inline_background_a.html"
+ }
+ ],
"css/inline_block_baseline_a.html": [
{
"path": "css/inline_block_baseline_a.html",
diff --git a/tests/ref/inline_background_a.html b/tests/wpt/mozilla/tests/css/inline_background_a.html
similarity index 87%
rename from tests/ref/inline_background_a.html
rename to tests/wpt/mozilla/tests/css/inline_background_a.html
index 58a34046d5d..31b45aabe15 100644
--- a/tests/ref/inline_background_a.html
+++ b/tests/wpt/mozilla/tests/css/inline_background_a.html
@@ -1,6 +1,7 @@
+