Minor comment changes, comment out all the speculative code for now

manage_display.module

@@ -16,6 +16,7 @@ use Drupal\node\Entity\NodeType;
  */
 function manage_display_entity_type_build(array &$entity_types) {
   $entity_types['node']->set('node_basefield_skip_preprocess', TRUE);
+
   // Set user name as a label else it gets printed twice on the user page.
   $keys = $entity_types['user']->get('entity_keys');
   $keys['label'] = 'name';
@@ -67,32 +68,32 @@ function manage_display_entity_base_field_info_alter(&$base_field_definitions, E
 /**
  * Implements hook_entity_view().
  */
-function manage_display_entity_view(array &$build, EntityInterface $entity, EntityViewDisplayInterface $display, $view_mode) {
-  if ($entity instanceof FieldableEntityInterface) {
-    $label_field = $entity->getEntityType()->getKey('label');
-    if (isset($build[$label_field])) {
-      //$build[$label_field]['#pre_render'][] = 'manage_display_title_pre_render';
-      // @todo If want to keep the field in the entity.
-      // Requires a change to EntityViewController::buildTitle
-      // $build['#built_page_title'] = TRUE;
-      // @todo If also want to hide title block.
-      // But loses metadata - better to prevent only title block.
-      // $build['#title'] = '';
-      //??$build['#title'] = new HtmlEscapedText($entity->label());
-    }
-  }
-}
+// function manage_display_entity_view(array &$build, EntityInterface $entity, EntityViewDisplayInterface $display, $view_mode) {
+//   if ($entity instanceof FieldableEntityInterface) {
+//     $label_field = $entity->getEntityType()->getKey('label');
+//     if (isset($build[$label_field])) {
+//       $build[$label_field]['#pre_render'][] = 'manage_display_title_pre_render';
+//       @todo If want to keep the field in the entity.
+//       Requires a change to EntityViewController::buildTitle
+//       $build['#built_page_title'] = TRUE;
+//       @todo If also want to hide title block.
+//       But loses metadata - better to prevent only title block.
+//       $build['#title'] = '';
+//       ??$build['#title'] = new HtmlEscapedText($entity->label());
+//     }
+//   }
+// }
 
 /**
  * Implements pre_render callback for entity.
  */
-function manage_display_title_pre_render(array $build) {
-  if (isset($build['#is_page_title'])) {
-    // @todo Ensure markup is inline: swap formatter etc. Workaround for https://www.drupal.org/node/2941208.
-    // Is this too late, as it has already been built?  Instead hook_entity_view_display_alter?
-  }
-  return $build;
-}
+// function manage_display_title_pre_render(array $build) {
+//   if (isset($build['#is_page_title'])) {
+//     // @todo Ensure markup is inline: swap formatter etc. Workaround for https://www.drupal.org/node/2941208.
+//     // Is this too late, as it has already been built?  Instead hook_entity_view_display_alter?
+//   }
+//   return $build;
+// }
 
 /**
  * Return information about the base fields that can be managed.
@@ -163,6 +164,7 @@ function template_preprocess_submitted(&$variables) {
     $variables['date']['#inline_field'] = TRUE;
     $variables['date'] = \Drupal::service('renderer')->render($variables['date']);
     // @todo This doesn't fully work with quickedit - when the field gets re-rendered after edit, the date is missing.
+    // Detect this case with a field preprocess hook and make a call to render the date.
     // Drupal core doesn't fully work either: the user picture doesn't get re-rendered.
   }
 }
@@ -171,6 +173,7 @@ function template_preprocess_submitted(&$variables) {
  * Implements hook_preprocess_node().
  */
 function manage_display_preprocess_node(&$variables) {
+  // @todo generalise this to any entity type.  Read entity_keys to find the field names.
   // Move date into the created element.
   if (isset($variables['content']['uid']['#formatter']) && ($variables['content']['uid']['#formatter'] == 'submitted')) {
     if (isset($variables['content']['created'])) {