Pablo López
--- a/core/modules/navigation/navigation.post_update.php
+++ b/core/modules/navigation/navigation.post_update.php
 */
 function navigation_post_update_set_logo_dimensions_default(array &$sandbox) {
  $settings = \Drupal::configFactory()->getEditable('navigation.settings');
-  $settings->set('logo_height', 40)
-    ->set('logo_width', 40);
+  if (!$settings->get('logo_height')) {
+    $settings->set('logo_height', 40);
+  }
+  if (!$settings->get('logo_width')) {
+    $settings->set('logo_width', 40);
+  }
  if (is_array($settings->get('logo_managed'))) {
    $settings->set('logo_managed', current($settings->get('logo_managed')));
  }
--- a/core/modules/navigation/src/Form/SettingsForm.php
+++ b/core/modules/navigation/src/Form/SettingsForm.php
+    $values = $form_state->getValues();
+    try {
+      if (!empty($values['logo_upload'])) {
+        $filename = $this->fileSystem->copy($values['logo_upload']->getFileUri(), $default_scheme . '://');
+        $values['logo_path'] = $filename;
+      }
    }
-
-    $width = $config->get('logo.max.width');
-    $height = $config->get('logo.max.height');
-
-    // Skip if the fid has not been modified.
-    $fid = reset($logo_managed);
-    if ($fid == $config->get('logo.managed')) {
+    catch (FileException) {
+      $this->messenger->deleteByType(MessengerInterface::TYPE_STATUS);