In Drupal 8, classes that are used in order to implement a content entity (which extend the ContentEntityBase class) have a validate() method that validates the values entered when creating the entity.
A similar method should be introduced in Backdrop and added to EntityInterface.
GitHub Issue #:
6061
Recent comments
I am having the same problem trying to update from 1.33.2 to 1.34.0 Error: Class 'CoreUpdater' not found in installer_authorize_batch_copy_project()
Error: Class "ModuleUpdater" not found
I adjusted the subject slightly.
CKEditor Inline Images not saved as Permanent in Term descriptions
It looks like it's a known issue with a PR. You might want to test this PR and respond in the issue itself.
CKEditor Inline Images not saved as Permanent in Term descriptions