diff --git a/mozilla/layout/reftests/bugs/421710-1.html b/mozilla/layout/reftests/bugs/421710-1.html
new file mode 100644
index 00000000000..f80138c7709
--- /dev/null
+++ b/mozilla/layout/reftests/bugs/421710-1.html
@@ -0,0 +1,226 @@
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/loose.dtd">
+<html class="reftest-print">
+<head>
+<style>
+#spContainer {
+clear: both;
+float: left !important;
+margin:0 !important;
+padding: 0 0 0 22px !important;
+min-width: 980px;
+max-width: 3000px;
+}
+.spSmallScreen #spMainContent {
+float: left !important;
+margin: 20px 12px 10px 0;
+padding: 0 0 0 0;
+width: 422px !important;
+clear:left;
+overflow: hidden;
+}
+.spSmallScreen #spColumnRight {
+float: left !important;
+margin: 0;
+width: 339px !important;
+background-repeat: repeat-y;
+background-position: top left;
+padding:0;
+overflow: hidden;
+}
+.spBigScreen #spColumnRight ul.spSingle,
+.spBigScreen #spColumnRight ul.spSplit,
+.spBigScreen #spColumnRight ul.spSplitRight {
+width: 220px !important;
+list-style: none;
+}
+.spBigScreen #spColumnRight ul.spSingle li,
+.spBigScreen #spColumnRight ul.spSplit li {
+width: 220px !important;
+float: none !important;
+}
+.spInfoBox {
+float: left;
+margin: 0 0 0 1px;
+padding: 13px 10px 15px 11px  !important;
+width: 317px;
+}
+.spInfoBox table{
+width: 280px !important;
+}
+ul.spSingle,
+ul.spSplit,
+ul.spSplitRight {
+float: left;
+padding: 0;
+width: 155px !important;
+margin: 11px 0 0 1px;
+list-style: none;
+}
+ul.spSplitRight {
+width: 142px !important;
+margin: 13px 0 0 11px !important;
+}
+#spBreadcrumbLine {
+width: 772px;
+height: auto;
+padding: 10px 0 8px 0;
+font-size: 0.625em;
+text-align: right;
+line-height: 1em;
+}
+.spArticleCredit{
+float: left;
+margin: 0;
+padding: 0;
+width: 100%;
+font-size: 0.8333em !important;
+line-height: 1.2em;
+text-align: right;
+}
+</style>
+</head>
+<body>
+<br clear="all">
+<div id="spContainer" class="spSmallScreen">
+<div id="spBreadcrumbLine">
+<br clear="all">
+</div>
+<div id="spMainContent">
+<div class="spArticleCredit">
+</div>
+<br clear="all">
+</div>
+
+<div id="spColumnRight">
+<div class="spInfoBox">
+<h5><a href=""></a></h5>
+<div id="spTop3KastenReiter">
+<ul>
+</ul>
+</div>
+<div id="spTop3daten">
+<ul class="spSplit">
+<li><h6>Gestresste Eltern: Hauen und Stechen in der Chancengesellschaft</h6>
+<div style="width: 140px">
+<img src="" width="140" height="80" />
+<div style="width:142px;">
+<div align="right" class="spCredit">AP</div>
+</div>
+
+</div>
+</li>
+</ul>
+<ul class="spSplitRight">
+</ul>
+</div>
+<br clear="all" />
+</div>
+<br clear="all" />
+<br clear="all">
+<br clear="all">
+<br>
+<div class="spInfoBox">
+<h5>SPIEGEL-DOSSIERS</h5>
+<ul class="spSplit">
+  <li>
+
+    <h6>Oskar Lafontaine: Der rote Panther</h6>
+    <div style="width: 140px;">
+    <img src="" height="80"  width="140">
+    <div style="width: 142px;">
+    <div class="spCredit" align="right">DPA</div>
+    </div>
+    </div>
+  </li>
+
+</ul>
+</div>
+<br clear="all">
+<br clear="all">
+<div class="spInfoBox">
+<h5>SPIEGEL special Geschichte</h5>
+<div style="clear: left;" align="center">
+<div style="width: 140px;">
+ <img src="" height="185" width="140"></div>
+</div>
+</div>
+<br clear="all">
+<div class="spInfoBox">
+<h5>SERVICE-ANGEBOTE</h5>
+
+<div>
+<table cellpadding="0" cellspacing="0" width="100%">
+  <tbody>
+    <tr>
+      <td><img src=""></td>
+      <td><img src=""></td>
+      <td><img src=""></td>
+      <td>Immobilien-<br> B&ouml;rse</td>
+
+    </tr>
+    <tr>
+      <td><img src=""></td>
+      <td>Lotto</td>
+      <td><img src=""></td>
+      <td>Banken-<br>Vergleiche</td>
+      <td><img src=""></td>
+
+      <td>Partnersuche</td>
+    </tr>
+    <tr>
+      <td><img src=""></td>
+      <td>Sportwetten</td>
+      <td><img src=""></td>
+      <td>Versicherungs-<br>Vergleiche</td>
+
+      <td><img src=""></td>
+      <td>Automarkt</td>
+    </tr>
+    <tr>
+      <td><img src=""></td>
+      <td><img src=""></td>
+      <td>Kostenloses<br>Girokonto</td>
+
+      <td><img src=""></td>
+      <td>Kfz-<br>Versicherung</td>
+    </tr>
+    <tr>
+      <td><img src=""></td>
+      <td><img src=""></td>
+      <td><img src=""></td>
+      <td>Brutto-Netto-<br>Rechner</td>
+
+    </tr>
+    <tr>
+      <td><img src=""></td>
+      <td><img src=""></td>
+      <td>Prozesskosten-<br>Rechner</td>
+      <td><img src=""></td>
+      <td>Uni-Tools</td>
+
+    </tr>
+    <tr>
+      <td><img src="" alt="SPIEGEL ONLINE"></td>
+      <td><img src=""></td>
+      <td><img src="" alt="SPIEGEL ONLINE"></td>
+    </tr>
+    <tr>
+      <td><img src=""></td>
+      <td>W&auml;hrungs-<br>Rechner</td>
+
+      <td><img src=""></td>
+    </tr>
+    <tr>
+      <td>H&ouml;rbuch-<br>Downloads</td>
+  </tbody>
+</table>
+</div>
+</div>
+</div>
+
+</div>
+<br clear="all">
+<br>
+<br clear="all">
+</body>
+</html>
diff --git a/mozilla/layout/reftests/bugs/reftest.list b/mozilla/layout/reftests/bugs/reftest.list
index 5b70d119a7d..7bbf29aa568 100644
--- a/mozilla/layout/reftests/bugs/reftest.list
+++ b/mozilla/layout/reftests/bugs/reftest.list
@@ -776,6 +776,7 @@ fails == 413027-3.html 413027-3-ref.html
 == 421069-ref.html 421069-ref2.html
 == 421234-1.html 421234-1-ref.html
 == 421419-1.html 421419-1-ref.html
+!= 421710-1.html about:blank     # assertion test (and crash test)
 == 421885-1.xml 421885-1-ref.xml
 == 421955-1.html 421955-1-ref.html
 == 422249-1.html 422249-1-ref.html

			Immobilien- Börse
	Lotto		Banken- Vergleiche		Partnersuche
	Sportwetten		Versicherungs- Vergleiche		Automarkt
		Kostenloses Girokonto		Kfz- Versicherung
			Brutto-Netto- Rechner
		Prozesskosten- Rechner		Uni-Tools

	Währungs- Rechner
Hörbuch- Downloads