Unable to reference event instances

A (very ugly) work around, that i added in a custom updatehook:

  $entity_type = 'eventinstance';

  $field_storage_definition = BaseFieldDefinition::create('string')
    ->setName('title')
    ->setLabel(t('Mock-title field'))
    ->setDescription(t('This is a mock title field, unused and read only. It is required, for eventinstances to work with entity reference autocomplete fields.'))
    ->setReadOnly(TRUE)
    ->setRevisionable(FALSE);

  \Drupal::entityDefinitionUpdateManager()
    ->installFieldStorageDefinition('title', $entity_type, $entity_type, $field_storage_definition);

  return "Mock title field has been added to the $entity_type entity.";

Yea this is a problem. There's a core issue around computed fields in entity queries: 🐛 Handle computed fields in entity queries: throwing a helpful exception is better than a PHP fatal error Needs work but the solution there is to just throw and handle an exception, that won't make this work.

The workaround above worries me because I feel like it could break inheritance completely in certain circumstances. I may have to think on this one, maybe even to the point of creating a custom event instance reference field so we can control things better.