diff --git a/templates/layout.html b/templates/layout.html
index eb94498..69fa822 100644
--- a/templates/layout.html
+++ b/templates/layout.html
@@ -82,7 +82,7 @@ __        ____________________
             <li class="footer__navitem -first">
                 <p>Folgt uns auf:<br>
                   <a href="https://chaos.social/@HackerGeno" title="Mastodon">
-                    {%- if '/images/mastodon_logo.svg'|asseturl -%}
+                    {%- if '/images/mastodon_logo.svg'|asseturl is defined -%}
                       <img alt="Mastodon Logo" class="footer__social_logo" src="{{ '/images/mastodon_logo.svg'|asseturl }}"/>
                     {%- else -%}
                       Mastodon
@@ -91,14 +91,14 @@ __        ____________________
                 </p>
                 <p>Abonniere unseren Podcast:<br>
                   <a href="https://vebit.xyz/podcast/" title="Podcast">
-                    {%- if '/images/wtf_podcast_logo.svg'|asseturl -%}
+                    {%- if '/images/wtf_podcast_logo.svg'|asseturl is defined -%}
                       <img alt="WTF Podcast Logo" class="footer__social_logo" src="{{ '/images/wtf_podcast_logo.svg'|asseturl }}"/>
                     {%- else -%}
                       Podcast
                     {%- endif -%}
                   </a>
                   <a href="https://vebit.xyz/wtf.xml" title="Podcast Feed">
-                    {%- if '/images/rss_feed.svg'|asseturl -%}
+                    {%- if '/images/rss_feed.svg'|asseturl is defined -%}
                       <img alt="Podcast Feed" class="footer__social_logo" src="{{ '/images/rss_feed.svg'|asseturl }}"/>
                     {%- else -%}
                       Podcast Feed
@@ -123,5 +123,7 @@ __        ____________________
         </ul>
       </div>
     </footer>
-    <script type="text/javascript" src="{{ '/js/nav_toggle.js'|url }}"></script>
+    {%- if '/js/nav_toggle.js'|asseturl is defined -%}
+      <script type="text/javascript" src="{{ '/js/nav_toggle.js'|asseturl }}"></script>
+    {%- endif %}
 </body>