diff --git a/previewers/betatest/HDF5Preview.html b/previewers/betatest/HDF5Preview.html
index 102187c..188f72e 100644
--- a/previewers/betatest/HDF5Preview.html
+++ b/previewers/betatest/HDF5Preview.html
@@ -7,7 +7,6 @@
     <title>H5Web</title>
 
     <meta name="description" content="Web-based HDF5 file viewer." />
-    <script src="https://polyfill.io/v3/polyfill.min.js?features=globalThis"></script>
     <script type="module" crossorigin src="./js/hdf5.js"></script>
     <link rel="stylesheet" href="./css/hdf5.css">
   </head>
diff --git a/previewers/v1.4/HDF5Preview.html b/previewers/v1.4/HDF5Preview.html
index 102187c..188f72e 100644
--- a/previewers/v1.4/HDF5Preview.html
+++ b/previewers/v1.4/HDF5Preview.html
@@ -7,7 +7,6 @@
     <title>H5Web</title>
 
     <meta name="description" content="Web-based HDF5 file viewer." />
-    <script src="https://polyfill.io/v3/polyfill.min.js?features=globalThis"></script>
     <script type="module" crossorigin src="./js/hdf5.js"></script>
     <link rel="stylesheet" href="./css/hdf5.css">
   </head>