Add $.unsafeWindow.

4chan_x.user.js

@@ -488,6 +488,11 @@
       $.add(d.head, script);
       return $.rm(script);
     },
+    unsafeWindow: window.opera && window || unsafeWindow || (function() {
+      d.createElement('p');
+      p.setAttribute('onclick', 'return window');
+      return el.onclick();
+    })(),
     shortenFilename: function(filename, isOP) {
       var threshold;
       threshold = isOP ? 40 : 30;

script.coffee

@@ -371,6 +371,12 @@ $.extend $,
       textContent: code
     $.add d.head, script
     $.rm script
+  # http://mths.be/unsafewindow
+  unsafeWindow: window.opera and window or unsafeWindow or (->
+    d.createElement 'p'
+    p.setAttribute 'onclick', 'return window'
+    el.onclick()
+  )()
   shortenFilename: (filename, isOP) ->
     # FILENAME SHORTENING SCIENCE:
     # OPs have a +10 characters threshold.