improve social media graph settings, and use nicer image

site/config.toml

@@ -13,7 +13,7 @@ DefaultContentLanguage = "en"
   url = "https://publiccode.eu"
 
 [params.sharemeta]
-  previewImage = "img/header.jpg"
+  previewImage = "img/share-graphics/imagine.jpg"
   fbPageID = "336939393138306"
   twitterUser = "@fsfe"
 

site/layouts/partials/head.html

@@ -12,22 +12,23 @@
   <link type="text/html" rel="alternate" hreflang="{{ .Lang }}" lang="{{ .Lang }}" href="{{ .RelPermalink }}" title="{{ .Site.Params.languageName }}">
 {{end}}
 
-{{ "<!-- Facebook meta-data -->" | safeHTML }}
+{{ "<!-- Open Graph meta-data (e.g. Facebook) -->" | safeHTML }}
+<meta property="og:type" content="website"/>
 <meta property="og:title" content="{{ .Site.Title }}"/>
-<meta property="og:url" content="{{ .Site.Params.url }}{{ .RelPermalink }}"/>
+<meta property="og:url" content="{{ .Site.Params.url }}"/>
 <meta property="og:image" content="{{ .Site.Params.url }}/{{ .Site.Params.Sharemeta.previewImage }}"/>
 <meta property="og:description" content="{{ .Site.Params.description }}"/>
-<meta property="og:type" content="website"/>
 <meta property="og:locale" content="{{ .Lang }}"/>
+{{ range .Translations }}<meta property="og:locale:alternate" content="{{.Lang }}"/>{{ end }}
 <meta property="fb:page_id" content="{{ .Site.Params.Sharemeta.fbPageID }}"/>
 
 {{ "<!-- Twitter meta-data -->" | safeHTML }}
-<meta name="twitter:title" content="{{ .Site.Title }}">
-<meta name="twitter:url" content="{{ .Site.Params.url }}{{ .RelPermalink }}">
-<meta name="twitter:image" content="{{ .Site.Params.url }}/{{ .Site.Params.Sharemeta.previewImage }}">
-<meta name="twitter:description" content="{{ .Site.Params.description }}">
-<meta name="twitter:card" content="summary">
+<meta name="twitter:card" content="summary_large_image">
 <meta name="twitter:site" content="{{ .Site.Params.Sharemeta.twitterUser }}">
+<meta name="twitter:title" content="{{ .Site.Title }}">
+<meta name="twitter:description" content="{{ .Site.Params.description }}">
+<meta name="twitter:image" content="{{ .Site.Params.url }}/{{ .Site.Params.Sharemeta.previewImage }}">
+<meta name="twitter:url" content="{{ .Site.Params.url }}">
 <meta name="twitter:creator" content="{{ .Site.Params.Sharemeta.twitterUser }}">
 
 {{ "<!-- Favicon -->" | safeHTML }}