Inline logo SVG.

core/modules/system/templates/block--system-branding-block.html.twig

@@ -18,7 +18,11 @@
 {% block content %}
   {% if site_logo %}
     <a href="{{ path('<front>') }}" rel="home">
-      <img src="{{ site_logo }}" alt="{{ 'Home'|t }}" fetchpriority="high" />
+      {% if site_logo|split('.')|last == "svg" %}
+        {% include site_logo %}
+      {% else %}
+        <img src="{{ site_logo }}" alt="{{ 'Home'|t }}" fetchpriority="high" />
+      {% endif %}
     </a>
   {% endif %}
   {% if site_name %}

core/themes/olivero/templates/block/block--system-branding-block.html.twig

@@ -18,7 +18,11 @@
   <div class="site-branding__inner">
     {% if site_logo %}
       <a href="{{ path('<front>') }}" rel="home" class="site-branding__logo">
-        <img src="{{ site_logo }}" alt="{{ 'Home'|t }}" fetchpriority="high" />
+        {% if site_logo|split('.')|last == "svg" %}
+          {% include site_logo %}
+        {% else %}
+          <img src="{{ site_logo }}" alt="{{ 'Home'|t }}" fetchpriority="high" />
+        {% endif %}
       </a>
     {% endif %}
     {% if site_name %}