Customer Email with diacritics isn't allowed

[Drakhunter]

Magento2 doesn't allow E-Mails with diacritics in CURL Requests.
According to wikipedia this should be allowed, but Magento is restricting it.

Is there a Fix or Workaround or something?

Preconditions

1. Magento Version 2.1.8

Steps to reproduce

1. get email address with diacritics (pepé@emailtest.com)
2. create json data object with email
   $data = [ 'customer' => [ 'email' => pepé@emailtest.com ] ]
3. create user using curl via /index.php/rest/V1/customers

Expected result

1. User should be created with correct email address

Actual result

1. {"message":"\"Email\" ist keine g\u00fcltige E-Mail-Adresse." (roughly translated: Email isn't a valid E-Mail-Address)

Additional Notes

Reproduced it via Swagger with using the following query /swagger#/customerAccountManagementV1/customerAccountManagementV1CreateAccountPost

The response is :

{
  "message": "\"Email\" is not a valid email address."
}

But this is also reproducible if try to create a customer from Magento Admin

[magento-engcom-team]

@Drakhunter, thank you for your report.
We've created internal ticket(s) MAGETWO-83378 to track progress on the issue.

[rparsi-boxycharm]

@magento-engcom-team any updates? We need a fix asap

[m2-assistant]

Hi @engcom-Bravo. Thank you for working on this issue.
Looks like this issue is already verified and confirmed. But if you want to validate it one more time, please, go though the following instruction:

• 1. Add/Edit Component: XXXXX label(s) to the ticket, indicating the components it may be related to.

• 2. Verify that the issue is reproducible on 2.4-develop branch

  Details

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• 3. If the issue is not relevant or is not reproducible any more, feel free to close it.

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[magento-engcom-team]

✅ Confirmed by @engcom-Bravo
Thank you for verifying the issue. Based on the provided information internal tickets MC-30334 were created

Issue Available: @engcom-Bravo, You will be automatically unassigned. Contributors/Maintainers can claim this issue to continue. To reclaim and continue work, reassign the ticket to yourself.

[ProkopovVitaliy]

@sdzhepa Looks like it is not bug this is default behavior. Even more, for this responsible not magento.

There is special class for validation Zend_Validate_EmailAddress his contain function where regular expression prohibits emails with such characters.

It is easy to fix but it is not Magento. So i think we can close current issue.

[rparsi-boxycharm]

@ProkopovVitaliy No, it is Magento because magento core code is using this. Magento customers such as myself need customer entity email addresses to support special characters like diacritics.
Magento team is responsible for fixing this.

[Alexander-Khohklov]

@magento I am working on this