The GnuPG command line and the GNU Privacy Assistant (in advanced mode) allow creating a PGP key pair (and adding a user ID to an existing key pair) without an email address (by leaving the email address field blank). i.e., the user ID is 'John Smith' rather than 'John Smith <email@example.com>'.

When attempting to create a PGP key pair or add a user ID to an existing key pair, Kleopatra marks the 'EMail' field '(required)' and gives the message 'EMail is required, but empty.' if no email is specified.

From what I can tell, the OpenPGP specification states the user ID 'by convention ... includes an RFC 2822 [RFC2822] mail name-addr, but there are no restrictions on its content.'

It would be very useful for me and my PGP community to be able to use Kleopatra to create a PGP key without an email address.

Reproducible: Always

Steps to Reproduce:
1. Use the File->New Certificate menu to attempt to create an OpenPGP key pair.
2. Give a suitable 'Name' but no 'EMail'.

Actual Results:  
The 'Next' button is greyed out and an 'EMail is required, but empty.' message appears.

Expected Results:  
Kleopatra should allow the key pair to be created with no email specified.