Why can't I use the digit "8" in e-mail addresses?
This is because the digit 8 is used as an alternative separator for plus addresses.
If you still want to use an "8" in your e-mail address, e.g. "user1980@example.com", create your address as "user19@example.com". You will then receive all e-mails sent to "user198...", i.e. not only "user1980@example.com" but also "user1988@example.com" or "user198helloworld@example.com".
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