Adjust 'Generate content' for mercury editor.

modules/schemadotorg_devel/src/SchemaDotOrgDevelGenerate.php

@@ -133,13 +133,13 @@ class SchemaDotOrgDevelGenerate implements SchemaDotOrgDevelGenerateInterface {
       }
     }
 
-    // Alter the Mercury Editor form.
+    // Alter the Mercury Editor form for new nodes.
     if (str_ends_with($form_id, 'mercury_editor_form')) {
       /** @var \Drupal\mercury_editor\Entity\MercuryEditorNodeForm $form_object */
       $form_object = $form_state->getFormObject();
       /** @var \Drupal\node\NodeInterface $node */
       $node = $form_object->getEntity();
-
+      if ($node->isNew()) {
         $url = Url::fromRoute('node.add', ['node_type' => $node->bundle()]);
         $query = $this->request()->query->all();
         if ($this->isDevelGenerateRequest()) {
@@ -162,6 +162,7 @@ class SchemaDotOrgDevelGenerate implements SchemaDotOrgDevelGenerateInterface {
         ];
       }
     }
+  }
 
   /**
    * Form element #after_build callback: Change the moderation state to published.