Sometimes there is a need to decorate StateTransitionValidation if logic is more complex than permission based.
There is as well few contrib modules which allows it.
As soon as you extend StateTransitionValidation it work, but when when you don't extend the class and implements StateTransitionValidationInterface, it returns error.
Best approach of decorators is that they should not extend classes, but use interface.
1. Add decorator which implements StateTransitionValidationInterface interface, and does not extends StateTransitionValidation.
Replace StateTransitionValidation with StateTransitionValidationInterface in WorkflowButtonsWidget.
Nothing.
Active
1.0
Code
Created pull request with solution. Attaching the patch as well if somebody needs it.