fix thumb selector for thread

boards/templates/boards/thread.html

@@ -25,7 +25,7 b''
             {% if post.image %}
                 <div class="image">
                     <a
-                            class="fancy"
+                            class="thumb"
                             href="{{ post.image.url }}"><img
                             src="{{ post.image.url_200x150 }}"
                             alt="{{ post.id }}"