Sitecore constructs the default URL of an item based on its 'name' and it can also be configured to use 'Display Name' instead.
There are Sitecore routines that prevent the content editor from typing Special characters on item names however, any character can be typed on a Display Name.
I have a scenario where the website has 3 languages and the URLs are built based on DisplayNames (useDisplayName set to true).
The content editors have been typing characters like áêã so I am creating my own routine to remove the special characters.
These characters are obviously not desired on a URL so that led me to think...
Is there a Sitecore routine or configuration that could prevent the user to type special characters on Display Name or all developers out there need to develop their own routine?