Unclear documentation about DNS reccord setting for CNAME on Gitla.com documentation

On the Gitlab documentation: https://docs.gitlab.com/ee/user/project/pages/getting_started_part_three.html

The documentation explains to the user:

Do not add any special chars after the default Pages domain. E.g., do not point your subdomain.domain.com to namespace.gitlab.io. or namespace.gitlab.io/.

However, a CNAME record that does not finish with a . will not be a valid record!

This could lead users to make mistakes in setting up their CNAME reccords.

However, Gitlab indicates the corect CNAME line when creating a custom domain, it's just in the documentation about the .