Contacts (Email) validation doesn't accept capital letters

[konradphoto]

Subject of the issue

While trying to generate the yml file, we encountered a validation error with Contacts (screenshot below). We removed the email address leaving the field empty and the Editor validated the file. However, upon the manual entry of the email address again, the editor generated the error. It appears the email validation doesn't accept CAPITAL letters. In some public organisations, there is a cultural of using ALL CAPS for last names or support mailboxes.

Steps to reproduce

1. Fill out properly all fields in the editor
2. In the section 8. Maintance, add Contacts with a Name and Email, such as [email protected]
3. Click on Generate
4. Error is generated: X Contacts

Expected behaviour

The Editor accepts capital leters in the email address and generates the YML File.

Actual behaviour

The Editor generates an error when there are capital letters in the email address