Inline Entity Form gives error after upgrading from 8.x-3.4 to 8.x-3.5.

Using Inline Entity Form 8.x-1.0-rc15 (latest version in 1 series) and Drupal 9.5.11 there is an error after updating CiviCRM entity from 8.x-3.4 to 8.x-3.5.

A complex entity reference field (which can embed nicely the event form in a node edit page), gives the error "Drupal\Component\Plugin\Exception\InvalidPluginDefinitionException: The "civicrm_event" entity type did not specify a inline_form handler. in Drupal\Core\Entity\EntityTypeManager->getHandler() (line 256 of /home/d8ietmx/public_html/core/lib/Drupal/Core/Entity/EntityTypeManager.php)." when editing or viewing the event.
When reverting to 8.x-3.4 everything works ok again.

field_civicrm_event:
type: inline_entity_form_complex
weight: 4
region: content
settings:
form_mode: default
override_labels: false
label_singular: ''
label_plural: ''
allow_new: true
allow_existing: true
match_operator: CONTAINS
allow_duplicate: false
collapsible: false
collapsed: false
revision: false
third_party_settings: { }