diff -u b/core/includes/theme.inc b/core/includes/theme.inc
--- b/core/includes/theme.inc
+++ b/core/includes/theme.inc
@@ -378,8 +378,8 @@
       if ($cache[$theme]->get('features.logo')) {
         $logo_path = $cache[$theme]->get('logo.path');
         if ($cache[$theme]->get('logo.use_default')) {
-          if (file_exists($theme_object->getPath() . '/logo.svg')) {
-            $cache[$theme]->set('logo.url', file_create_url($theme_object->getPath() . '/logo.svg'));
+          if ($logo_svg = file_exists($theme_object->getPath() . '/logo.svg')) {
+            $cache[$theme]->set('logo.url', file_create_url($logo_svg));
           }
           else {
             $cache[$theme]->set('logo.url', file_create_url($theme_object->getPath() . '/logo.png'));