This was quite the battle but I am able to take data from a backend that has nested arrays containing nested arrays and populate nested formArrays.
I was not able to find any blogs or StackOverflow posts that went this deep. I refactored the Reactive Forms Heroes example. In my case I only want one hero and I want multiple addresses. The problem was that I wanted each address to have multiple pets. So, the pets are children of the addresses. In my real-world problem, I have a questionnaire and that questionnaire has child topics and those topics have child questions.
If you happen to know of a better way, please do let me know.
The main meat here is in the Hero detail component and specifically the setAddresses() method. Also, the matching HTML structure in the view.
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