1 files changed, 30 insertions, 0 deletions
diff --git a/docshell/test/navigation/file_bug534178.html b/docshell/test/navigation/file_bug534178.html
new file mode 100644
index 0000000000..4d77dd824b
--- /dev/null
+++ b/docshell/test/navigation/file_bug534178.html
@@ -0,0 +1,30 @@
+<html>
+  <head>
+    <script>
+    
+      function testDone() {
+        document.body.firstChild.remove();
+        var isOK = false;
+        try {
+          isOK = history.previous != location;
+        } catch (ex) {
+          // history.previous should throw if this is the first page in shistory.
+          isOK = true;
+        }
+        document.body.textContent = isOK ? "PASSED" : "FAILED";
+        opener.ok(isOK, "Duplicate session history entries should have been removed!");
+        opener.finishTest();
+      }
+      function ifrload() {
+        setTimeout(testDone, 0);
+      }
+      function test() {
+        var ifr = document.getElementsByTagName("iframe")[0];
+        ifr.onload = ifrload;
+        ifr.src = "data:text/html,doc2";
+      }
+    </script>
+  </head>
+  <body onload="setTimeout(test, 0)"><iframe src="data:text/html,doc1"></iframe>
+  </body>
+</html>