diff --git a/layout/reftests/w3c-css/submitted/flexbox/flexbox-align-self-stretch-vert-1-ref.html b/layout/reftests/w3c-css/submitted/flexbox/flexbox-align-self-stretch-vert-1-ref.html
new file mode 100644
index 00000000000..3ffa8647bb2
--- /dev/null
+++ b/layout/reftests/w3c-css/submitted/flexbox/flexbox-align-self-stretch-vert-1-ref.html
@@ -0,0 +1,29 @@
+<!DOCTYPE html>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<!-- In this reference case, we just have the testcases's text placed directly
+     in the outermost wrapper-block, with a lime background on that wrapper
+     instead of on a flex item.
+-->
+<html>
+<head>
+  <title>CSS Reftest Reference</title>
+  <link rel="author" title="Daniel Holbert" href="mailto:dholbert@mozilla.com">
+  <meta charset="utf-8">
+  <style>
+    div.fixedWidthWrapper {
+      width: 200px;
+      /* Small enough that 3 characters can _easily_ fit in our width */
+      font-size: 12px;
+      background: lime;
+    }
+  </style>
+</head>
+<body>
+  <div class="fixedWidthWrapper">
+    A B C
+  </div>
+</body>
+</html>
diff --git a/layout/reftests/w3c-css/submitted/flexbox/flexbox-align-self-stretch-vert-1.html b/layout/reftests/w3c-css/submitted/flexbox/flexbox-align-self-stretch-vert-1.html
new file mode 100644
index 00000000000..97500acfd7c
--- /dev/null
+++ b/layout/reftests/w3c-css/submitted/flexbox/flexbox-align-self-stretch-vert-1.html
@@ -0,0 +1,49 @@
+<!DOCTYPE html>
+<!--
+     Any copyright is dedicated to the Public Domain.
+     http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<html>
+<head>
+  <title>CSS Test: Testing the sizing of a stretched horizontal flex container in a vertical flex container</title>
+  <link rel="author" title="Daniel Holbert" href="mailto:dholbert@mozilla.com">
+  <link rel="help" href="http://dev.w3.org/csswg/css-flexbox/#layout-algorithm">
+  <link rel="match" href="flexbox-align-self-stretch-vert-1-ref.html">
+  <meta name="assert" content="If a stretched flex item's main size is influenced by its cross size, and the flex container has a definite cross size, then the item's cross size should be resolved early so that it can be used when determining the item's main size">
+  <meta name="assert" content="http://dev.w3.org/csswg/css-flexbox/issues-cr-2012#issue-23">
+  <meta charset="utf-8">
+  <style>
+    div.fixedWidthWrapper {
+      width: 200px;
+      /* Small enough that 3 characters can _easily_ fit in our width */
+      font-size: 12px;
+    }
+    div.vertContainer {
+      display: flex;
+      flex-direction: column;
+    }
+    div.vertItem {
+      background: red;
+    }
+    div.horizContainer {
+      display: flex;
+    }
+    div.horizItem {
+      flex: 1;
+      background: lime;
+    }
+  </style>
+</head>
+<body>
+  <div class="fixedWidthWrapper">
+    <div class="vertContainer">
+      <div class="vertItem">
+        <div class="horizContainer">
+          <div class="horizItem">A B C</div>
+          <div class="horizItem"></div>
+        </div>
+      </div>
+    </div>
+  </div>
+</body>
+</html>
diff --git a/layout/reftests/w3c-css/submitted/flexbox/reftest.list b/layout/reftests/w3c-css/submitted/flexbox/reftest.list
index e8124b2233c..f39632d3802 100644
--- a/layout/reftests/w3c-css/submitted/flexbox/reftest.list
+++ b/layout/reftests/w3c-css/submitted/flexbox/reftest.list
@@ -1,6 +1,8 @@
 # Tests for cross-axis alignment (align-self / align-items properties)
 == flexbox-align-self-baseline-horiz-1.xhtml  flexbox-align-self-baseline-horiz-1-ref.xhtml
 
+== flexbox-align-self-stretch-vert-1.html flexbox-align-self-stretch-vert-1-ref.html
+
 == flexbox-align-self-horiz-1-block.xhtml  flexbox-align-self-horiz-1-ref.xhtml
 == flexbox-align-self-horiz-1-table.xhtml  flexbox-align-self-horiz-1-ref.xhtml
 == flexbox-align-self-horiz-2.xhtml  flexbox-align-self-horiz-2-ref.xhtml
