Welcome to the Microsoft Q&A Platform. Thank you for reaching out & I hope you are doing well.
I am afraid I did not understand your requirement here.
From your verbatim,
- You created a Static Web App with default domain : victorious-any-bla-bla.azurestaticapps.net
- You are planning to create a custom domain for this
- Your DNS Provider and Manager is GoDaddy.
When you say, "I attempted to create a custom domain in the Azure portal with the name: myapp.azurewebsites.net"
- This is not supported.
- The domain "azurewebsites.net" is owned by Azure and I am afraid it won't be possible for you to have purchased this domain "azurewebsites.net" from a DNS Registrar
- In this case, "myapp.azurewebsites.net" will never have a CNAME record to your static web app "victorious-any-bla-bla.azurestaticapps.net"
I hope this makes sense.
Cheers,
Kapil