{{ $cats := slice }}
{{ range .Site.Data.bookmarks }}
  {{ $cats = $cats | append .category }}
{{ end }}
{{ $cats = uniq $cats | sort }}
{{ range $cats }}
    {{ $cat := . }}
<h4>{{ $cat }}</h4>
    {{ range $.Site.Data.bookmarks }}
    {{ if eq .category $cat }}
<section data-post-type="bookmark-of" data-post-id="{{ .Params.slug }}" class="bookmark h-entry">
  <div class="author" style="display:none">
    <a rel="author" class="p-author h-card" rel="me" href="https://jk.nipponalba.scot"><img src="/images/profile.jpg"/><div class="title">{{ .Site.Params.Title }}</div></a>
  </div>
  <aside>
    <article class="h-cite">
      <u><a href="{{ .bookmarkof | absURL }}" class="u-bookmark-of" target="_blank">{{ .name }}</a></u> - <div class="p-name p-content">{{ .content | markdownify }}</div>
    </article>
  </aside>
</section>
{{ end }}
{{ end }}
{{ end }}