@Teodor Just a suggestion but that might be an easy fix for you guys. If you want to stick to CDNs or allow local script then you could add a fallback so that we can load a local script or you fall back to their other CDN if unpkg.com is not available:
So instead of:
<script src="http://unpkg.com/@yaireo/tagify" defer></script>
you could do:
<script src="http://unpkg.com/@yaireo/tagify" onerror="this.onerror=null;this.src='https://cdn.jsdelivr.net/npm/@yaireo/tagify';" defer></script>