--- a/layout/reftests/w3c-css/submitted/flexbox/flexbox-align-content-vert-001-ref.xhtml
+++ b/layout/reftests/w3c-css/submitted/flexbox/flexbox-align-content-vert-001-ref.xhtml
@@ -123,10 +123,38 @@
       <div class="b" style="margin-left: 80px"><div class="fixedSizeChild"/></div>
     </div>
     <div class="flexbox">
       <div class="a" style="margin-left: 20px"/>
       <div class="b" style="margin-left: 40px"><div class="fixedSizeChild"/></div>
       <div class="c" style="margin-left: 40px"/>
     </div>
 
+    <!-- left -->
+    <div class="flexbox">
+      <div class="a"/>
+    </div>
+    <div class="flexbox">
+      <div class="a"/>
+      <div class="b"><div class="fixedSizeChild"/></div>
+    </div>
+    <div class="flexbox">
+      <div class="a"/>
+      <div class="b"><div class="fixedSizeChild"/></div>
+      <div class="c"/>
+    </div>
+
+    <!-- right -->
+    <div class="flexbox">
+      <div class="a"/>
+    </div>
+    <div class="flexbox">
+      <div class="a" style="margin-left: 160px"/>
+      <div class="b"><div class="fixedSizeChild"/></div>
+    </div>
+    <div class="flexbox">
+      <div class="a" style="margin-left: 120px"/>
+      <div class="b"><div class="fixedSizeChild"/></div>
+      <div class="c"/>
+    </div>
+
   </body>
 </html>

--- a/layout/reftests/w3c-css/submitted/flexbox/flexbox-align-content-vert-001a.xhtml
+++ b/layout/reftests/w3c-css/submitted/flexbox/flexbox-align-content-vert-001a.xhtml
@@ -129,10 +129,38 @@
       <div class="b"><div class="fixedSizeChild"/></div>
     </div>
     <div class="flexbox" style="align-content: space-around">
       <div class="a"/>
       <div class="b"><div class="fixedSizeChild"/></div>
       <div class="c"/>
     </div>
 
+    <!-- left -->
+    <div class="flexbox" style="align-content: left">
+      <div class="a"/>
+    </div>
+    <div class="flexbox" style="align-content: left">
+      <div class="a"/>
+      <div class="b"><div class="fixedSizeChild"/></div>
+    </div>
+    <div class="flexbox" style="align-content: left">
+      <div class="a"/>
+      <div class="b"><div class="fixedSizeChild"/></div>
+      <div class="c"/>
+    </div>
+
+    <!-- right -->
+    <div class="flexbox" style="align-content: right">
+      <div class="a"/>
+    </div>
+    <div class="flexbox" style="align-content: right">
+      <div class="a"/>
+      <div class="b"><div class="fixedSizeChild"/></div>
+    </div>
+    <div class="flexbox" style="align-content: right">
+      <div class="a"/>
+      <div class="b"><div class="fixedSizeChild"/></div>
+      <div class="c"/>
+    </div>
+
   </body>
 </html>

--- a/layout/reftests/w3c-css/submitted/flexbox/flexbox-align-content-vert-001b.xhtml
+++ b/layout/reftests/w3c-css/submitted/flexbox/flexbox-align-content-vert-001b.xhtml
@@ -130,10 +130,38 @@
       <div class="b"><div class="fixedSizeChild"/></div>
     </div>
     <div class="flexbox" style="align-content: space-around">
       <div class="a"/>
       <div class="b"><div class="fixedSizeChild"/></div>
       <div class="c"/>
     </div>
 
+    <!-- left -->
+    <div class="flexbox" style="align-content: left">
+      <div class="a"/>
+    </div>
+    <div class="flexbox" style="align-content: left">
+      <div class="a"/>
+      <div class="b"><div class="fixedSizeChild"/></div>
+    </div>
+    <div class="flexbox" style="align-content: left">
+      <div class="a"/>
+      <div class="b"><div class="fixedSizeChild"/></div>
+      <div class="c"/>
+    </div>
+
+    <!-- right -->
+    <div class="flexbox" style="align-content: right">
+      <div class="a"/>
+    </div>
+    <div class="flexbox" style="align-content: right">
+      <div class="a"/>
+      <div class="b"><div class="fixedSizeChild"/></div>
+    </div>
+    <div class="flexbox" style="align-content: right">
+      <div class="a"/>
+      <div class="b"><div class="fixedSizeChild"/></div>
+      <div class="c"/>
+    </div>
+
   </body>
 </html>