Uncaught SyntaxError: missing ) after argument list

I’m seeing this error in the console when Async is enabled.

This is the source code it points to.

<script type='text/javascript'>
( 'fetch' in window ) || document.write( '<script defer='defer' src="https://rhondalevan.com/wp-includes/js/dist/vendor/wp-polyfill-fetch.min.js?ver=3.0.0"></scr' + 'ipt>' );( document.contains ) || document.write( '<script defer='defer' src="https://rhondalevan.com/wp-includes/js/dist/vendor/wp-polyfill-node-contains.min.js?ver=3.26.0-0"></scr' + 'ipt>' );( window.FormData && window.FormData.prototype.keys ) || document.write( '<script defer='defer' src="https://rhondalevan.com/wp-includes/js/dist/vendor/wp-polyfill-formdata.min.js?ver=3.0.12"></scr' + 'ipt>' );( Element.prototype.matches && Element.prototype.closest ) || document.write( '<script defer='defer' src="https://rhondalevan.com/wp-includes/js/dist/vendor/wp-polyfill-element-closest.min.js?ver=2.0.2"></scr' + 'ipt>' );
</script>

Is that being generated by Async?

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