Can github pages CNAME file contain more than one domain?
Example file:
reggi.com
www.reggi.com
blog.reggi.com
No, this is not possible. See the GitHub Help docs that explain this:
Ensure you only have one domain listed in your CNAME file. If you wish to have multiple domains pointing to the same Pages, you will need to set up redirects for the other domains. Most domain registrars and DNS hosts offer this service to their customers.