diff --git a/_includes/gallery.html b/_includes/gallery.html
index bf4effa165cf51dc2228f64d27bf7948a70d28c5..ddad39de68c0d15cf3b0b76ceb3f2a63f2dd6dcd 100644
--- a/_includes/gallery.html
+++ b/_includes/gallery.html
@@ -28,7 +28,11 @@
   {% if image.tags contains {{include.topic}} %}
     <figure itemprop="associatedMedia" itemscope itemtype="http://schema.org/ImageObject">
         <a href="{{image.picurl}}" itemprop="contentUrl" data-size="{{image.size | default: "600x400"}}">
+          {% if image.thumburl %}
+            <img src="{{image.thumburl}}" itemprop="thumbnail" alt="{{image.description}}" />
+          {% else %}
             <img src="{{image.picurl}}" itemprop="thumbnail" alt="{{image.description}}" />
+          {% endif %}
         </a>
         {% if image.author %}
           <figcaption itemprop="{{image.description}}">{{image.description}} ({{image.license}} {{image.author}})</figcaption>