Don't allow token reference with metatag module to destroy node/add pages

metatags-memory-fix.php

<?php

/**
 * Implements hook_form_alter().
 */
function hook_form_alter(&$form, &$form_state, $form_id) {
  // Deny access to view Metatag tokens if token memory consumption is out of
  // control. In one site build, this trimmed ~40mb off of memory required to
  // render the node/add page for a custom article page and took the total HTML
  // payload on another content type's node/add page from 7.18mb to 43.68kb.
  if (!empty($form['#node_edit_form']) && !empty($form['metatags'])) {
    $form['metatags']['tokens']['#access'] = FALSE;
  }
}