Design issue Ideographic space in username

[Mike]

To solve this bug http://stackoverflow.com/questions/3230623/filter-all-types-of-whitespace-in-php

 

[Brent W]

This isn't confusing at all....

 

[BamaStangGuy]

This isn't confusing at all....

Are you sure?

 

[chulapi]

Nice catch!
But after fixing the bug I think Mike (the real one) is going to ban you

 

[Mike]

In general, this isn't fixable at least not in the short term. This really is the "unicode confusables" issue so it goes way beyond spacing.

If you want to enforce a limit, a username regular expression will prevent it. Preventing it without that is much trickier. Otherwise, active moderation will need to be involved.