The summary display in the article list on the top page was being shown with the HTML notation still left in it, which felt wrong, so I fixed it ↓
Stripping the HTML also looks better for SEO, so I made the following change
layouts/partials/post_preview.html
<article class="post-preview">
<a href="{{ .Permalink }}">
<h2 class="post-title">{{ .Title }}</h2>
{{ if .Params.subtitle }}
<h3 class="post-subtitle">
{{ .Params.subtitle }}
</h3>
{{ end }}
{{ if .Params.image }}
<img src="{{ .Params.image }}" alt="{{ .Title }}" class="img-title" />
{{ end }}
{{ if .Params.video }}
<video loop autoplay muted playsinline class="img-title">
<source src="{{ .Params.video }}">
</video>
{{ end }}
</a>
<p class="post-meta">
{{ partial "post_meta.html" . }}
</p>
<div class="post-entry">
{{ if or (.Truncated) (.Params.summary) }}
{{ .Summary | plainify }}
<a href="{{ .Permalink }}" class="post-read-more">[{{ i18n "readMore" }}]</a>
{{ else }}
{{ .Content }}
{{ end }}
</div>
{{ if .Params.tags }}
<div class="blog-tags">
{{ range .Params.tags }}
<a href="{{"tags" | absLangURL}}/{{ . | urlize }}/">{{ . }}</a>
{{ end }}
</div>
{{ end }}
</article>