diff -r 000000000000 -r 6474c204b198 browser/components/shell/test/browser_633221.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/components/shell/test/browser_633221.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,15 @@
+function test() {
+  let osString = Cc["@mozilla.org/xre/app-info;1"].
+                 getService(Ci.nsIXULRuntime).OS;
+
+  // this test is Linux-specific
+  if (osString != "Linux")
+    return;
+
+  let shell = Cc["@mozilla.org/browser/shell-service;1"].
+              getService(Ci.nsIShellService);
+
+  shell.setDefaultBrowser(true, false);
+  ok(shell.isDefaultBrowser(true, false), "we got here and are the default browser");
+  ok(shell.isDefaultBrowser(true, true), "we got here and are the default browser");
+}