diff --git a/tests/ref/basic.list b/tests/ref/basic.list
index 9c0d759e842..c0fb11df27c 100644
--- a/tests/ref/basic.list
+++ b/tests/ref/basic.list
@@ -96,7 +96,6 @@ prefs:"layout.writing-mode.enabled" == iframe/size_attributes_vertical_writing_m
!= image_rendering_auto_a.html image_rendering_pixelated_a.html
== image_rendering_pixelated_a.html image_rendering_pixelated_ref.html
-== img_block_display_a.html img_block_display_ref.html
== img_block_maxwidth_a.html img_block_maxwidth_ref.html
== img_block_maxwidth_b.html img_block_maxwidth_ref.html
!= img_simple.html img_simple_ref.html
diff --git a/tests/wpt/mozilla/meta/MANIFEST.json b/tests/wpt/mozilla/meta/MANIFEST.json
index 999b761f294..6d05263397e 100644
--- a/tests/wpt/mozilla/meta/MANIFEST.json
+++ b/tests/wpt/mozilla/meta/MANIFEST.json
@@ -803,6 +803,18 @@
"url": "/_mozilla/css/flex_nochild.html"
}
],
+ "css/img_block_display_a.html": [
+ {
+ "path": "css/img_block_display_a.html",
+ "references": [
+ [
+ "/_mozilla/css/img_block_display_ref.html",
+ "=="
+ ]
+ ],
+ "url": "/_mozilla/css/img_block_display_a.html"
+ }
+ ],
"css/img_dynamic_remove.html": [
{
"path": "css/img_dynamic_remove.html",
@@ -4764,6 +4776,18 @@
"url": "/_mozilla/css/flex_nochild.html"
}
],
+ "css/img_block_display_a.html": [
+ {
+ "path": "css/img_block_display_a.html",
+ "references": [
+ [
+ "/_mozilla/css/img_block_display_ref.html",
+ "=="
+ ]
+ ],
+ "url": "/_mozilla/css/img_block_display_a.html"
+ }
+ ],
"css/img_dynamic_remove.html": [
{
"path": "css/img_dynamic_remove.html",
diff --git a/tests/wpt/mozilla/tests/css/100x100_green.png b/tests/wpt/mozilla/tests/css/100x100_green.png
new file mode 100644
index 00000000000..b23bbba154e
Binary files /dev/null and b/tests/wpt/mozilla/tests/css/100x100_green.png differ
diff --git a/tests/ref/img_block_display_a.html b/tests/wpt/mozilla/tests/css/img_block_display_a.html
similarity index 88%
rename from tests/ref/img_block_display_a.html
rename to tests/wpt/mozilla/tests/css/img_block_display_a.html
index 95808589bc5..5e3071ac1e0 100644
--- a/tests/ref/img_block_display_a.html
+++ b/tests/wpt/mozilla/tests/css/img_block_display_a.html
@@ -1,6 +1,7 @@
+