bibcite_entity_update_8028 causes : "Mismatched entity and/or field definitions"

I would also like to hear about this. I just ran into the same thing and had to use 'drush entup', after searching the admin UI fruitlessly for this Abstract field, which seems to be baked into the Bibcite module and not exposed in the admin UI. I looked through all my Bibcite types' fields, and elsewhere, before resorting to 'drush entup'.

When I ran "drush db" this is what I saw:

"bibcite_reference entity type :
The Abstract field needs to be updated."

So this is a field on the Bibcite module's entity type itself.

It seems to me this 'Abstract' field update should be handled by a Bibcite module DB update, not Devel Entity Updates.

The cause for this, is the change introduced by following issue:
PubMed abst_e field - contains basic html (3079282) →

The abstract fields (english and french) have been changed changed from text (long) to text (formatted, long).
It seems that something is missing in the update hook for the english abstract field.

This was committed back in December, but the issue was never set to fixed. Additionally, I don't think it received a proper review. This is the update hook that was committed:

/**
 * Update entity definitions.
 */
function bibcite_entity_update_8029() {
  $entity_type_manager = \Drupal::entityTypeManager();
  $entity_type_manager->clearCachedDefinitions();

  $entity_type_ids = [];
  $change_summary = \Drupal::service('entity.definition_update_manager')->getChangeSummary();
  foreach ($change_summary as $entity_type_id => $change_list) {
    $entity_type = $entity_type_manager->getDefinition($entity_type_id);
    \Drupal::entityDefinitionUpdateManager()->installEntityType($entity_type);
    $entity_type_ids[] = $entity_type_id;
  }

  return t("Installed/Updated the entity type(s): @entity_type_ids", [
    '@entity_type_ids' => implode(', ', $entity_type_ids),
  ]);
}

This is not the correct way of handling the problem.

1. It uses the entity definition update manager to install entity types, but the entity types are already installed. It should use ->updateEntityType()
2. It should not load all entity definitions that require and update! It should only modify those that the bibcite_entity module is responsible for. This is dangerous.
3. It should not simply load the version of the entity definition from code and re-install/update it. It needs to figure out the precise change that is needed and apply that change instead. Otherwise, if someone updated from this version of bibcite to one in the future that also made changes to the entity definition, resetting the entity definition to the current code's representation may cause major conflicts and issues. That's why drush removed this "quick fix" command to begin with.

This update hook should be modified to address the specific change in the entity definition that was needed.