While updating the database (using drush updb), it breaks on bibcite_entity_update_8014:
[error] Error: Class 'Drupal\entity\Routing\RevisionRouteProvider' not found in Drupal\Core\Entity\EntityTypeManager->createHandlerInstance() (line 276 of /var/www/project/web/core/lib/Drupal/Core/Entity/EntityTypeManager.php) #0 /var/www/project/web/core/lib/Drupal/Core/Entity/EntityTypeManager.php(231): Drupal\Core\Entity\EntityTypeManager->createHandlerInstance()
Update all modules to the latest core 8
Upgrade to 9.2.2
Run 'drush updb'
Closed: works as designed
1.0
Code
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It's likely this issue predates Contrib.social: some issue and comment data are missing.
It seems highly likely that this problem was caused by the Entity API module not being installed. Given that this original poster has not responded and the issue has not been commented on in 4 years, I'm going to close this as "Works as designed."