How to secure the frontend from XSS through the registration form?

Question

JavaScript

Hello. Such a question: the user types in the login text field, which is immediately sent to the server to check for the existence of such.
The problem is that when you enter, for example, https://toster.ru/ , the script will be executed, how to secure this behavior for the frontend part? Escape characters?
Thanks for your help and your time.

Answer 1

when you enter, for example, https://toster.ru/ the script will be executed

What script? Why did you do that?
Yes, filter or escape the data. In general, it would be nice to escape all user-generated content.