I have a backend that does not support emoji characters in all of its fields, so I want to block them directly in the frontend application. I'm in the register section, and I want to limit the possible characters for the email field.
I know that RFC 5322 specifies that many particularities can be found in those addresses, including special characters. Even emoji can be put there (link).
I'm using a whitelist to implement this block.
What character should I whitelist to support the common emails without falling into whitelisting every characters supported by email addresses?