diff --git a/doc/_themes/sphinx13/static/_sphinx_javascript_frameworks_compat.js b/doc/_themes/sphinx13/static/_sphinx_javascript_frameworks_compat.js
index 8549469dc..fc4ad89b3 100644
--- a/doc/_themes/sphinx13/static/_sphinx_javascript_frameworks_compat.js
+++ b/doc/_themes/sphinx13/static/_sphinx_javascript_frameworks_compat.js
@@ -9,11 +9,6 @@
  *
  */
 
-/**
- * select a different prefix for underscore
- */
-$u = _.noConflict();
-
 
 /**
  * small helper function to urldecode strings