How to reproduce

• Add a service to propose a content (for example classified ads)
• Do not set a result page
• define the front-office edition new style on the project
• Go to front-office
• Submit a classified ad

Actual behavior

• The default result page is displayed "Votre contenu a été créé avec succès"
• few seconds later an error occurred
• 

  Caused by: org.ametys.plugins.repository.AmetysRepositoryException: An object id must conform to the <protocol>://<protocol-specific-part> syntax:
          at org.ametys.plugins.repository.AmetysObjectResolver.resolveById(AmetysObjectResolver.java:306)
          at org.ametys.plugins.frontedition.DispatchGenerator._setContextInRequestAttributes(DispatchGenerator.java:58)
          at org.ametys.core.ui.dispatcher.DispatchGenerator._dispatching(DispatchGenerator.java:130)
          at org.ametys.core.ui.dispatcher.DispatchGenerator.generate(DispatchGenerator.java:95)
          at org.apache.cocoon.components.pipeline.AbstractProcessingPipeline.processXMLPipeline(AbstractProcessingPipeline.java:581)
  

Front edition shoud check that it is not a real page.