diff --git a/molecules-and-light_en.html b/molecules-and-light_en.html
index a6eac68..6735692 100644
--- a/molecules-and-light_en.html
+++ b/molecules-and-light_en.html
@@ -115,7 +115,6 @@
 
   if ( brand === 'phet-io' ) {
     preloads = preloads.concat( [
-      '../chipper/js/phet-io/phetioCompareAPIs.js',
       '../phet-io/js/phet-io-initialize-globals.js',
       '../molecules-and-light/js/molecules-and-light-phet-io-overrides.js'
     ] );