diff --git a/layout/style/test/file_flexbox_min_size_auto.html b/layout/style/test/file_flexbox_min_size_auto.html
index 5902e139f076..e4a73c98030d 100644
--- a/layout/style/test/file_flexbox_min_size_auto.html
+++ b/layout/style/test/file_flexbox_min_size_auto.html
@@ -1,9 +1,17 @@
 <!DOCTYPE HTML>
 <html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=763689
+-->
 <head>
   <meta charset="utf-8">
+  <title>Test behavior of 'min-height:auto' and 'min-width:auto' (Bug 763689)</title>
+  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
 </head>
 <body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=763689">Mozilla Bug 763689</a>
+<body>
 <div id="display">
   <div id="non-flex-item">abc</div>
   <div style="display: flex">
@@ -52,11 +60,6 @@
  * min-content height as needed in layout.)
  */
 
-// Use "is()", "ok()", and "todo_is()" from parent document.
-var is = parent.is;
-var ok = parent.ok;
-var todo_is = parent.todo_is;
-
 // Given an element ID, this function sets the corresponding
 // element's inline-style min-width and min-height explicitly to "auto".
 function setElemMinSizesToAuto(aElemId) {
@@ -119,9 +122,6 @@ function checkAllTheMinSizes() {
 
 // Main test function
 function main() {
-  ok(SpecialPowers.getBoolPref("layout.css.flexbox.enabled"),
-     "expecting to be run with flexbox support enabled");
-
   // First: check that min-sizes are what we expect, with min-size properties
   // at their initial value.
   checkAllTheMinSizes();
@@ -134,8 +134,6 @@ function main() {
 
   // ...and try again (should have the same result):
   checkAllTheMinSizes();
-
-  parent.finish();
 }
 
 main();
diff --git a/layout/style/test/mochitest.ini b/layout/style/test/mochitest.ini
index bea622f4a915..13c5b7c2ff95 100644
--- a/layout/style/test/mochitest.ini
+++ b/layout/style/test/mochitest.ini
@@ -128,8 +128,7 @@ skip-if = toolkit == 'android' #bug 536603
 [test_flexbox_flex_shorthand.html]
 [test_flexbox_layout.html]
 support-files = flexbox_layout_testcases.js
-[test_flexbox_min_size_auto.html]
-support-files = file_flexbox_min_size_auto.html
+# [test_flexbox_min_size_auto.html] # (will uncomment in next patch)
 [test_flexbox_order.html]
 [test_flexbox_order_table.html]
 [test_font_face_parser.html]
diff --git a/layout/style/test/test_flexbox_min_size_auto.html b/layout/style/test/test_flexbox_min_size_auto.html
deleted file mode 100644
index b7b4fd144304..000000000000
--- a/layout/style/test/test_flexbox_min_size_auto.html
+++ /dev/null
@@ -1,43 +0,0 @@
-<!DOCTYPE HTML>
-<html>
-<!--
-https://bugzilla.mozilla.org/show_bug.cgi?id=763689
--->
-<head>
-  <meta charset="utf-8">
-  <title>Test behavior of 'min-height:auto' and 'min-width:auto' (Bug 763689)</title>
-  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
-  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
-</head>
-<body>
-<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=763689">Mozilla Bug 763689</a>
-<div id="display">
-  <iframe id="iframe"></iframe>
-</div>
-<pre id="test">
-<script type="application/javascript">
-"use strict";
-
-/** Test 'min-height:auto' and 'min-width:auto' (Bug 763689) **/
-
-/*
- * This mochitest runs in an iframe so that we can selectively turn on the
- * flexbox about:config pref before its document is instantiated.
- *
- * See the iframe's source ("file_flexbox_min_size_auto.html") for the actual
- * test code and for more documentation.
- */
-
-SimpleTest.waitForExplicitFinish();
-
-SpecialPowers.setBoolPref("layout.css.flexbox.enabled", true);
-document.getElementById("iframe").src = "file_flexbox_min_size_auto.html";
-
-function finish() {
-  SpecialPowers.clearUserPref("layout.css.flexbox.enabled");
-  SimpleTest.finish();
-}
-</script>
-</pre>
-</body>
-</html>
