Firebase hosting custom domain error

I observed this error when migrating a domain between two Firebase projects quickly.

I resolved it by following these steps:

1. Remove all Firebase related DNS records from your DNS provider
2. Unlink your custom domain from your current project's hosting console
3. Start the linking process again. The TXT records may have changed, so double check them before applying them to your DNS configuration
4. Wait 5-10 minutes and re-verify your custom domain with your Firebase project.

5. Verify that the TXT records are propagated -- You can check using dig TXT example.com on command line, or a web tool like this one. The TXT records should look similar to this:

   ;QUESTION
   example.com. IN TXT
   ;ANSWER
   example.com. 299 IN TXT "firebase=examplefirebase"
   example.com. 299 IN TXT "globalsign-domain-verification=21qwertyjklRSFsjalkfe432dswlaGgi2Bafsad"
   

This was a known problem and has been RESOLVED by the Firebase team.

Michael Bleigh: We're working on a capacity issue with the domain provisioning system.

Tracked on the group discussion "Can't get custom domain to verify"