Punycode in registration email is not allowed

1dollarsteak

When registering while supplying an email address, that contains punycode with two dashes
(https://en.wikipedia.org/wiki/Punycode), the form returns an error, that this email is already in use or might not be in a correct format.

Examples of punycode are:

It should continue to create an account.

1dollarsteak

I've continued testing. I believe that the pattern verification process is explicitly stuck on the double dashes in a punycode email domain (xn-- ...). This is prefixed to domains that contain special characters (see examples above).

I've edited the examples above to make the problem clearer. If I can be of further assistance, please let me know.

All the best,
🥩