Experimental knowledge base actions

Is the experimental Knowledge Base Actions still supported? I noticed that the documentation is no longer at https://rasa.com/docs/action-server/knowledge-bases/. And the github repo at GitHub - RasaHQ/tutorial-knowledge-base: Integrating Rasa with a knowledge base to encode domain knowledge and resolve entities no longer works as Grakn has changed their name to TypeDB. Also, the chapter 6 example from Conversational AI with Rasa (2021, Kong & Wang), Conversational-AI-with-RASA/Chapter06 at main · PacktPublishing/Conversational-AI-with-RASA · GitHub, no longer works with Rasa 3. So would like to know if this is no longer supported or are their plans to update these resources.