I have a suspicion that Block inside a Block produces System.StackOverflowException. It happens only while developing on localhost, but not on a production when uploaded to server.
I have a Content Area on a Page-1 where I create a Block-1 -> which has a Content Area where I create a different block (Block-2).
That same Block-2 when used in Content Area on any other page works.
However that Block-2 if not nested inside Block-1, and used on the same Page-1 still fires StackOverflowException.
What are your thoughts on this? I don't know how to debug this.
Have you changed the property type?
Like - initially you defined the property with some other type and then change it to ContentArea.