Code highlighting compresses blocks into single line

[hallstig]

Whenever I use code highlighting for code blocks they keep getting mangled into one long line when publishing the page. During preview while editing it works as expected.

Looking into what gets published I see the following which I think should have rendered properly.
<pre><code class="language-c">lots of code on a long line here</code></pre>

Currently using the Prism Highglight plugin version 1.5.0 on Quark 2.0.4 with Grav 1.7.37.1, installed via the Grav skeleton blog site bundle. I have previously tried with the grav Highlight and PHP highlighter too with the same result.

I tried to be as detailed as possible, let me know if I can help by providing more information or trying something out.

Cheers!