diff --git a/doc/vimwiki.txt b/doc/vimwiki.txt
index 239a9f1..b7f6d93 100644
--- a/doc/vimwiki.txt
+++ b/doc/vimwiki.txt
@@ -1521,7 +1521,7 @@ In this case, <mathjax_folder> would be "../mathjax" (without quotes).
 2. Loading MathJax from a CDN-server (needs internet connection).
 Add to your HTML template the following lines:
 
-<script src="https://polyfill.io/v3/polyfill.min.js?features=es6"></script>
+<script src="https://cdnjs.cloudflare.com/polyfill/v3/polyfill.min.js?features=es6"></script>
 <script id="MathJax-script" async src="https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml-chtml.js"></script>