Are there browsers that don't support maxlength?

Question

I have a contest entry page on my company\'s website. In order to enter the contest, you create a login, which is just an email and a 4-digit pin. Here\'s the PIN field:

Answer 1

I believe that every browser supports it, here's a few links for reference :

Maxlength | SitePointReference

Maxlength | W3 Schools

Obviously there are way around this - you should ensure you ALWAYS have adequate server-side validation, as client-side usually isn't enough on it's own.