diff --git a/content/io.js b/content/io.js
index fdc14d2d..1481c864 100644
--- a/content/io.js
+++ b/content/io.js
@@ -474,8 +474,9 @@ liberator.IO = function () //{{{
             var file = Components.classes["@mozilla.org/file/local;1"]
                                  .createInstance(Components.interfaces.nsILocalFile);
 
-            var tmpname = liberator.config.name.toLowerCase() + "-" +
-                window.content.document.location.hostname + ".tmp";
+            if (window.content.document.location.hostname)
+                var tmpname = liberator.config.name.toLowerCase() + "-" +
+                    window.content.document.location.hostname + ".tmp";
             if (liberator.config.name == "Muttator")
                 tmpname = "mutt-ator-mail"; // to allow vim to :set ft=mail automatically