Thanks for your question. You found the most appropriate place to post it as well!
The Qlik Community uses QlikID Single-Sign-On, so email addresses cannot be changed within the community.
To update the email address on your community account, you'll need to work with Customer Support (firstname.lastname@example.org) and they will be able update the email address on your QlikID SSO account. This change will get carried over into the community at your next login.
I've emailed Customer Support for you, and so they will be reaching out to you shortly.
Qlik Community Team