Allow overriding branding_logo on the 404 page

docs/advanced_topics/customisation/admin_templates.rst

@@ -43,6 +43,8 @@ To replace the default logo, create a template file ``dashboard/templates/wagtai
         <img src="{% static 'images/custom-logo.svg' %}" alt="Custom Project" width="80" />
     {% endblock %}
 
+The logo also appears on the admin 404 error page; to replace it there too, create a template file ``dashboard/templates/wagtailadmin/404.html`` that overrides the ``branding_logo`` block.
+
 ``branding_favicon``
 --------------------
 

wagtail/wagtailadmin/templates/wagtailadmin/404.html

@@ -13,7 +13,9 @@
 {% block furniture %}
     <div class="page404__bg">
         <div class="page404__wrapper">
-            {% include "wagtailadmin/shared/animated_logo.html" %}
+            {% block branding_logo %}
+                {% include "wagtailadmin/shared/animated_logo.html" %}
+            {% endblock %}
 
             <div class="page404__text-container">
                 <h1 class="page404__header">