Add listener for may-blank, may-blank-within classes based on JS config.

r2/r2/public/static/js/ui.js

@@ -32,6 +32,15 @@ r.ui.init = function() {
         $(el).data('SubredditSubmitText', new r.ui.SubredditSubmitText({el: el}))
     })
 
+    if (r.config.new_window) {
+        $(document.body).on('click', 'a.may-blank, .may-blank-within a', function() {
+            if (!this.target) {
+                this.target = '_blank'
+            }
+            return true // continue bubbling
+        })
+    }
+
     r.ui.PermissionEditor.init()
 }