diff --git a/mkdocs.yml b/mkdocs.yml
index 32fdb38..159db8b 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -47,7 +47,6 @@ extra_css:
   
 extra_javascript:
   - javascripts/config.js
-  - https://polyfill.io/v3/polyfill.min.js?features=es6
   - https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml-chtml.js
 
 nav:
@@ -58,4 +57,4 @@ nav:
     - Run the App Package: 'exec/run.md'
     - Run the released App Package: 'exec/run_release.md'
 
-copyright: <a href="https://img.shields.io/badge/License-CC_BY--SA_4.0-lightgrey.svg">License CC BY-SA 4.0</a>, by <a href="https://creativecommons.org/licenses/by-sa/4.0/">Creative Commons</a>
\ No newline at end of file
+copyright: <a href="https://img.shields.io/badge/License-CC_BY--SA_4.0-lightgrey.svg">License CC BY-SA 4.0</a>, by <a href="https://creativecommons.org/licenses/by-sa/4.0/">Creative Commons</a>