Why has Leaflet JS suddenly stopped working?

This is no longer showing a map on the front-end.

It works fine in the back-end.

Here is the code that manifests in the front…

<div class="leaflet-map" data-height="350" data-map="leaflet" data-map-lng="7.0174313" data-map-lat="43.5507876" data-map-zoom="14" data-map-layers="[&quot;OpenStreetMap&quot;]" data-map-markers="[{&quot;label&quot;:&quot;Palais des Festivals, Boulevard de la Croisette, Cannes, France&quot;,&quot;default_label&quot;:&quot;&quot;,&quot;lat&quot;:43.5507815,&quot;lng&quot;:7.0174321}]"></div>

The following stylesheet is included at the bottom, and goes to a working file…

<link rel="stylesheet" id="leaflet-css" href="https://www.example.com/wp-content/plugins/acf-openstreetmap-field/assets/css/leaflet.min.css?ver=1.1.9" type="text/css" media="all">

That is with the Leaflet JS render setting enabled.

The iFrame render setting actually still works.

I don’t see any leaflet.js-type file at the bottom of source.