diff --git a/src/CoreBundle/Resources/views/Layout/head.html.twig b/src/CoreBundle/Resources/views/Layout/head.html.twig
index ce1b3479f0..9868c7fef8 100644
--- a/src/CoreBundle/Resources/views/Layout/head.html.twig
+++ b/src/CoreBundle/Resources/views/Layout/head.html.twig
@@ -31,7 +31,7 @@
         {{ encore_entry_link_tags('vue') }}
         {{ encore_entry_link_tags('app') }}
 
-        {% if color_theme_link %}
+        {% if color_theme_link is defined %}
             {{ color_theme_link|raw }}
         {% endif %}