Using files from assets instead of external urls for fixed versions

[rimvislt]

Is it possible to move external files from https://github.com/vb64/django.admin.geomap/blob/main/django_admin_geomap/templates/geomap/osm/base.html

<!-- Pointer events polyfill for old browsers, see https://caniuse.com/#feat=pointer -->
<link rel="stylesheet" href="https://cdn.jsdelivr.net/gh/openlayers/openlayers.github.io@master/en/v6.15.1/css/ol.css" type="text/css" />
<script src="https://cdn.jsdelivr.net/gh/openlayers/openlayers.github.io@master/en/v6.15.1/build/ol.js"></script>

<script src="https://code.jquery.com/jquery-3.5.1.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.5.0/js/bootstrap.bundle.min.js"></script>

to assets, because it is fixed versions and it is blocked by "Content-Security-Policy" by default.

This requires to add exemptions for fixed versions URLs on all servers.

[vb64]

Of course, it is possible.

But we need to figure out the best way to do it in order to maintain backward compatibility with existing installations.

Do you have any suggestions?