diff --git a/plugins/_collections.js b/plugins/_collections.js
index 3348dcb12..fab928799 100644
--- a/plugins/_collections.js
+++ b/plugins/_collections.js
@@ -2291,7 +2291,8 @@ exports.editorNamespaces = [
     'http://ns.adobe.com/Flows/1.0/',
     'http://ns.adobe.com/ImageReplacement/1.0/',
     'http://ns.adobe.com/GenericCustomNamespace/1.0/',
-    'http://ns.adobe.com/XPath/1.0/'
+    'http://ns.adobe.com/XPath/1.0/',
+    'http://schemas.microsoft.com/visio/2003/SVGExtensions/'
 ];
 
 // http://www.w3.org/TR/SVG/linking.html#processingIRI