Unicode, emojis, and input validation☠️

Should you just stick to basic ASCII stuff for databases? For usernames, user input (such as posts), passwords, etc. Or should you embrace unicode and all of the potential problems it can cause? I've heard of some people saying they even have emojis in their passwords. I guess that makes it more secure in the sense that there are more combinations for any given password length, but at the same time, sometimes there are weird issues with unicode characters, like that one iOS bug that caused phones to crash when they received a combination of left-to-right and right-to-left Unicode characters.It could be a potential security issue too, or there might be issues with deserialization as well.

I would imagine ASCII-only makes regular expression easier too. I don't even know all of the characters in Unicode, or how you would test for certain ranges of characters. Plus, Unicode adds new characters all the time.

What are your thoughts on this?

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I’m a 25 year old boomer and I think everything should be ASCII just like the good old days at Bell Labs.