When using a profile with an email on a contribution page email is not included in green box on thank you page

It used to that the billing email was required on all contribution pages and would show up at the top of the page with no configuration. That email was named "email-{bltID}" where blt ID is the billing profile id

In newer versions of civi if you have an email in the profile you are using on the contribution page civi will remove the billing email (ex: email-5) from the top of the page in preference to the one in the profile. If the one in the profile is not named email-{bltID} then in the green box on the thank you page it will not know what email to print and will say "An email has been sent to ."