Use site.title in og:title if page.title is not set

Philippus · Philippus · commit aa3dfdaa9a23 · 2018-10-21T23:34:23.000+02:00
diff --git a/_includes/headertop.html b/_includes/headertop.html
@@ -1,9 +1,11 @@
 <!DOCTYPE html>
 <html>
   <head>
-    <title>{% if page.title %}{{ page.title }} | {% endif %}{{ site.title }}</title> 
+    <title>{% if page.title %}{{ page.title }} | {% endif %}{{ site.title }}</title>
     {% if page.title %}
     <meta property="og:title" content="{{ page.title }}"/>
+    {% else %}
+    <meta property="og:title" content="{{ site.title }}"/>
     {% endif %}
     {% if page.description %}
     <meta name="description" content="{{ page.description }}"/>
