Variables and options must be escaped when echo'd

[emanuellopess]

There are a number of options to secure all types of content (html, email, etc). Yes, even HTML needs to be properly escaped.

https://developer.wordpress.org/apis/security/escaping/

Remember: You must use the most appropriate functions for the context. There is pretty much an option for everything you could echo. Even echoing HTML safely.

fee-recovery-for-givewp/includes/class-fee-recovery-for-givewp-activator.php:65 echo $message;