GraphViz array visible but no actual graph drawn

We have the module loaded and configured on our Drupal 11.4.5 site.

Technical details of system under test

Drupal 11.4.4
A custom subtheme Bootstrap5 (Bootstrap5 v4.05)
Apache/2.4.62 (Win64) OpenSSL/3.0.15 mod_fcgid/2.3.9
PHP 8.3.26
PHP Memory limit: 512M
MySQL 8.4.3
PHP Caching module: OpCache

We a content type called 'Tutorial' (machine name: tutorial) and it has multiple Entity Reference fields to:

• Content nodes.
• Paragraphs
• Taxonomy terms.

That's why we so interested in be able to visualise the connections!

As an illustration let's look at just one of those fields…

We a field called 'Prerequisites' (machine name: prerequisites) (1)

It connects to a single content node (2)...

When a node of this type (1) is rendered, the referenced content entity is clearly visible..

We have configured the module to show us the GraphViz object but when we go to view the Content Tree (1), we see that object (2) but the actual graph does not render at all (3)...

We also see...

A quick look into the browser's Console shows...

Same things as pure text…

GET https://webgraphviz.com/viz.js net::ERR_CERT_AUTHORITY_INVALID
Failed to load resource: net::ERR_CERT_AUTHORITY_INVALID vis.js:1

jquery.min.js?v=4.0.0:2 jQuery.Deferred exception ReferenceError: Viz is not defined
    at HTMLDocument.<anonymous> (graphviz.js?tji1h3:8:19)
    at l (jquery.min.js?v=4.0.0:2:24813)
    at c (jquery.min.js?v=4.0.0:2:25132) undefined
T.Deferred.exceptionHook @ jquery.min.js?v=4.0.0:2
c @ jquery.min.js?v=4.0.0:2
setTimeout
(anonymous) @ jquery.min.js?v=4.0.0:2
c @ jquery.min.js?v=4.0.0:2
add @ jquery.min.js?v=4.0.0:2
(anonymous) @ jquery.min.js?v=4.0.0:2
Deferred @ jquery.min.js?v=4.0.0:2
then @ jquery.min.js?v=4.0.0:2
T.fn.ready @ jquery.min.js?v=4.0.0:2
attach @ graphviz.js?tji1h3:6
(anonymous) @ drupal.js?v=11.4.5:166
Drupal.attachBehaviors @ drupal.js?v=11.4.5:162
(anonymous) @ drupal.init.js?v=11.4.5:32
listener @ drupal.init.js?v=11.4.5:20
jquery.min.js?v=4.0.0:2 Uncaught ReferenceError: Viz is not defined
    at HTMLDocument.<anonymous> (graphviz.js?tji1h3:8:19)
    at l (jquery.min.js?v=4.0.0:2:24813)
    at c (jquery.min.js?v=4.0.0:2:25132)
(anonymous) @ graphviz.js?tji1h3:8
l @ jquery.min.js?v=4.0.0:2
c @ jquery.min.js?v=4.0.0:2
setTimeout
(anonymous) @ jquery.min.js?v=4.0.0:2
c @ jquery.min.js?v=4.0.0:2
add @ jquery.min.js?v=4.0.0:2
(anonymous) @ jquery.min.js?v=4.0.0:2
Deferred @ jquery.min.js?v=4.0.0:2
then @ jquery.min.js?v=4.0.0:2
T.fn.ready @ jquery.min.js?v=4.0.0:2
attach @ graphviz.js?tji1h3:6
(anonymous) @ drupal.js?v=11.4.5:166
Drupal.attachBehaviors @ drupal.js?v=11.4.5:162
(anonymous) @ drupal.init.js?v=11.4.5:32
listener @ drupal.init.js?v=11.4.5:20
jquery.min.js?v=4.0.0:2 Uncaught Error: Provided selector did not find any elements. Selector: #graphviz_svg_div svg
    at Object.getSvg (svg-pan-zoom.min.js:3:27738)
    at c (svg-pan-zoom.min.js:3:22813)
    at HTMLDocument.<anonymous> (svg_zoom.js?tji1h3:6:40)
    at l (jquery.min.js?v=4.0.0:2:24813)
    at c (jquery.min.js?v=4.0.0:2:25132)
getSvg @ svg-pan-zoom.min.js:3
c @ svg-pan-zoom.min.js:3
(anonymous) @ svg_zoom.js?tji1h3:6
l @ jquery.min.js?v=4.0.0:2
c @ jquery.min.js?v=4.0.0:2
setTimeout
(anonymous) @ jquery.min.js?v=4.0.0:2
c @ jquery.min.js?v=4.0.0:2
add @ jquery.min.js?v=4.0.0:2
(anonymous) @ jquery.min.js?v=4.0.0:2
Deferred @ jquery.min.js?v=4.0.0:2
then @ jquery.min.js?v=4.0.0:2
T.fn.ready @ jquery.min.js?v=4.0.0:2
attach @ svg_zoom.js?tji1h3:5
(anonymous) @ drupal.js?v=11.4.5:166
Drupal.attachBehaviors @ drupal.js?v=11.4.5:162
(anonymous) @ drupal.init.js?v=11.4.5:32
listener @ drupal.init.js?v=11.4.5:20

Can anyone shed any light onto what is or isn't causing this?

Thank you