Some weird error symbol on the first character when using REGEXP_ONLY_DIGITS_AND_CHARS / REGEXP_ONLY_CHARS pattern

[aryaadinulfadlan]

I found a tiny weird error symbol (maybe) in the shadcn/ui documentation https://ui.shadcn.com/docs/components/input-otp.
It happens when I type letters of the alphabet while using the REGEXP_ONLY_DIGITS_AND_CHARS / REGEXP_ONLY_CHARS pattern.
the error symbol only appear on the first character.

how to remove that error symbol ?
that's quite annoying.