message: Fix no featured image in <head> regression
  We didn't think of these when implementing
diff: {{ $authors = delimit (apply (apply . "index" $.Site.Params.authors ".") "index" "." "byline") ", " (T "blog-and") }}
  {{ end }}
  +{{ $img_src := "" }}
  +{{ if .Params.featured_image }}
  + <!-- 1200x630 seems to be a good size for all platform (see https://iamturns.com/open-graph-image-size/). -->
  + {{ $img_src = (partial "functions/imgURL" (dict "page" .Page "name" (.Params.featured_image) "command" "Fill" "options" "1200x630 Center Box")) }}
  +{{ else if .Params.featured_image_url }}
  + {{ $img_src = .Params.featured_image_url }}
  +{{ end }}
  +
  <link href="{{ "blog/index.xml" | absURL }}" rel="alternate" type="application/rss+xml" title="{{ .Site.Title }}" />
  <link href="{{ "blog/index.xml" | absURL }}" rel="feed" type="application/rss+xml" title="{{ .Site.Title }}" />
  <meta itemprop="name" content="{{ $title }}">
  <meta itemprop="description" content="{{ if .Description }}{{ .Description }}{{ else }}{{if .IsPage }}{{ .Summary }}{{ end }}{{ end }}">
  {{ with .Params.tags }}<meta itemprop="keywords" content="{{ delimit (first 6 .) ", " }}" />{{ end }}
  -{{ with .Params.featuredImage }}<meta itemprop="image" content="{{ . | absURL }}">{{ end }}
  +{{ with $img_src }}<meta itemprop="image" content="{{ . | absURL }}">{{ end }}
  {{ if .Params.authors }}<meta itemprop="author" content="{{ $authors }}">{{ end }}
  <meta itemprop="datePublished" content="{{ dateFormat "2006-01-02" $date }}">
  {{ with .Params.tags }}{{ range first 6 . -}}
  <meta property="article:tag" content="{{ . }}" />
  {{ end }}{{ end }}
  -{{ with .Params.featured_image }}<meta property="og:image" content="{{ . | absURL }}">
  +{{ with $img_src }}
  +<meta property="og:image" content="{{ . | absURL }}">
  +{{ end }}
  +<!-- If the image was specified as a Hugo page resource, we have resized it and know the actual dimensions. -->
  +{{ if .Params.featured_image }}
  +<meta property="og:image:width" content="1200">
  +<meta property="og:image:height" content="630">
  {{ end }}
  <!-- Twitter cards -->
  -{{- with .Params.featured_image }}
  +{{- with $img_src }}
  <meta name="twitter:card" content="summary_large_image">
  <meta name="twitter:image" content="{{ . | absURL }}">
  {{- else }}
  