Have you written an Apache Sling Rewriter module for AEM?Apache Sling :: Output Rewriting Pipelines (org.apache.sling.rewriter)

As we stated - replace your datasource with the article that Ratna pointed you too that uses WCMUsePojo!

Your issue is not reproducible. AEM does let you save with no values - see:

Hey Jessie - start with this KB - Optimize AEM Site Performance

Also - check this article - we perform JCR operations here -- Modifying Digital Assets using Adobe Experience Manager Workflows

Can you post a video of your component so we can understand how its functioning.  I am not completely sure what you mean by: "I need to prevent this "tabcontent" from being deleted, how can I do that?"See this article that works with Multifield and Sling Models - i am seeing no issue here working wi...

I will test this tomorrow to see if we can cast to JCR Session and use it to interact with JCR operations.

See the following video that shows this working when using WCMUsePojo

See this -- How to get jcr Session in the workflow? To whitelist the bundle - see this -- Scott's Digital Community: Adobe Experience Manager FAQs and other Tips  (Search whitelist)

Show full code example please