Fixed open graph image URL

material/overrides/main.html

@@ -7,7 +7,7 @@
   {% if page and page.title and not page.is_homepage %}
     {% set title = config.site_name ~ " - " ~ page.title | striptags %}
   {% endif %}
-  {% set image = 'assets/images/material.png' | url %}
+  {% set image = config.site_url ~ 'assets/images/material.png' %}
   <meta property="og:title" content="{{ title }}">
   <meta property="og:description" content="{{ config.site_description }}">
   <meta property="og:url" content="{{ page.canonical_url }}">

mkdocs.yml

@@ -22,7 +22,8 @@
 site_name: Material for MkDocs
 site_description: A Material Design theme for MkDocs
 site_author: Martin Donath
-site_url: https://squidfunk.github.io/mkdocs-material/
+site_url: https://deploy-preview-1486--mkdocs-material-preview.netlify.com/
+#site_url: https://squidfunk.github.io/mkdocs-material/
 
 # Repository
 repo_name: squidfunk/mkdocs-material

src/overrides/main.html

@@ -31,8 +31,8 @@
     {% set title = config.site_name ~ " - " ~ page.title | striptags %}
   {% endif %}
 
-  <!-- Determine image -->
-  {% set image = 'assets/images/material.png' | url %}
+  <!-- The image needs to have an absolute URL -->
+  {% set image = config.site_url ~ 'assets/images/material.png' %}
 
   <!-- Open graph meta tags -->
   <meta property="og:title" content="{{ title }}" />