diff --git a/layout/html/tests/table/bugs/bug222846.html b/layout/html/tests/table/bugs/bug222846.html
new file mode 100644
index 00000000000..263eac513ad
--- /dev/null
+++ b/layout/html/tests/table/bugs/bug222846.html
@@ -0,0 +1,29 @@
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
+    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
+<html>
+<head>
+<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
+<title>table dom test</title>
+<style type="text/css">
+  table {width:200px}
+table[summary="summ"] {font-size:24pt}
+</style>
+<script type="text/javascript">
+function dom(){
+var t = document.getElementById('t2');
+t.summary="summ";
+}
+</script>
+</head>
+
+<body onload="dom()">
+
+Both tables should look identical
+
+<table id="t2" border><caption>caption</caption><tbody><tr><td>cell1</td></tr></tbody></table>
+
+<table id="t2" summary="summ" border><caption>caption</caption><tbody><tr><td>cell1</td></tr></tbody></table>
+
+</body>
+
+</html>
diff --git a/layout/html/tests/table/bugs/file_list3.txt b/layout/html/tests/table/bugs/file_list3.txt
index f19880ae012..b9bf9667d8d 100644
--- a/layout/html/tests/table/bugs/file_list3.txt
+++ b/layout/html/tests/table/bugs/file_list3.txt
@@ -16,6 +16,7 @@ file:///s|/mozilla/layout/html/tests/table/bugs/bug22246-2.html
 file:///s|/mozilla/layout/html/tests/table/bugs/bug22246-2a.html
 file:///s|/mozilla/layout/html/tests/table/bugs/bug22246-3.html
 file:///s|/mozilla/layout/html/tests/table/bugs/bug22246-3a.html
+file:///s|/mozilla/layout/html/tests/table/bugs/bug222846.html
 file:///s|/mozilla/layout/html/tests/table/bugs/bug2267.html
 file:///s|/mozilla/layout/html/tests/table/bugs/bug22513.html
 file:///s|/mozilla/layout/html/tests/table/bugs/bug2296.html
