Why ban emoji in username?

account42 2 days ago | parent | next [-]

You typically want a bijection from rendered glyphs to binary representation and restricting to ASCII is the most straight forward way to achieve that.

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afiori 3 days ago | parent | prev | next [-]

My reasoning for it would be that they can be very keyboard specific and might require more normalisation than other character classes.

If I had to make a specific choice I would probably whitelist the most common emojis for some definition and allow those

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pas 4 days ago | parent | prev | next [-]

I think for username it's fine, where a bit of restraint makes sense is for billing/shipping/legal-ish data.

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numpad0 3 days ago | parent | prev [-]

Because username and password MUST be in ASCII range?

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Timwi 3 days ago | parent [-]

No.

	▲	numpad0 3 days ago \| parent [-]
		How no? UTF-8 strings has no singular canonical binary representations and typing sequences that correspond to intended texts. Which means it can't be hashed and compared for authentication purposes. No?