diff --git a/tests/wpt/mozilla/tests/css/button_css_width.html b/tests/wpt/mozilla/tests/css/button_css_width.html
new file mode 100644
index 00000000000..8013fca55c0
--- /dev/null
+++ b/tests/wpt/mozilla/tests/css/button_css_width.html
@@ -0,0 +1,8 @@
+<!DOCTYPE html>
+<html>
+<head>
+<link rel='match' href='button_css_width_ref.html'>
+</head>
+<body>
+<button style="width: 200px">foo</button>
+</body>
diff --git a/tests/wpt/mozilla/tests/css/button_css_width_ref.html b/tests/wpt/mozilla/tests/css/button_css_width_ref.html
new file mode 100644
index 00000000000..8e4ef5646be
--- /dev/null
+++ b/tests/wpt/mozilla/tests/css/button_css_width_ref.html
@@ -0,0 +1,3 @@
+<!DOCTYPE html>
+<html>
+<input type="button" style="width: 200px" value="foo">
