diff --git a/browser/base/content/tabbrowser.xml b/browser/base/content/tabbrowser.xml
index 82a5f0881d5..18cfe83ffa0 100644
--- a/browser/base/content/tabbrowser.xml
+++ b/browser/base/content/tabbrowser.xml
@@ -1912,7 +1912,7 @@
                   /^\s*(javascript|data):/.test(url))
                 return;
 
-              this.dragDropSecurityCheck(aEvent, aDragSession, url);
+              nsDragAndDrop.dragDropSecurityCheck(aEvent, aDragSession, url);
 
               var bgLoad = true;
               try {
@@ -2310,51 +2310,7 @@
         <parameter name="aUri"/>
         <body>
           <![CDATA[
-            // Do a security check for drag n' drop. Make sure the
-            // source document can load the dragged link.
-            var sourceDoc = aDragSession.sourceDocument;
-
-            if (sourceDoc) {
-              // Strip leading and trailing whitespace, then try to
-              // create a URI from the dropped string. If that
-              // succeeds, we're dropping a URI and we need to do a
-              // security check to make sure the source document can
-              // load the dropped URI. We don't so much care about
-              // creating the real URI here (i.e. encoding differences
-              // etc don't matter), we just want to know if aUri
-              // really is a URI.
-
-              var uriStr = aUri.replace(/^\s*|\s*$/g, '');
-              var uri = null;
-
-              try {
-                uri = Components.classes["@mozilla.org/network/io-service;1"]
-                  .getService(Components.interfaces.nsIIOService)
-                  .newURI(uriStr, null, null);
-              } catch (e) {
-              }
-
-              if (uri) {
-                // aUri is a URI, do the security check.
-                var sourceURI = sourceDoc.documentURI;
-
-                const nsIScriptSecurityManager =
-                  Components.interfaces.nsIScriptSecurityManager;
-                var secMan =
-                  Components.classes["@mozilla.org/scriptsecuritymanager;1"]
-                  .getService(nsIScriptSecurityManager);
-
-                try {
-                  secMan.checkLoadURIStr(sourceURI, uriStr,
-                                         nsIScriptSecurityManager.STANDARD);
-                } catch (e) {
-                  // Stop event propagation right here.
-                  aEvent.stopPropagation();
-
-                  throw "Drop of " + aUri + " denied.";
-                }
-              }
-            }
+            nsDragAndDrop.dragDropSecurityCheck(aEvent, aDragSession, aUri);
           ]]>
         </body>
       </method>
