Email validation by way of FILTER_VALIDATE_EMAIL behaves differently depending on PHP version/installation · Issue #897 · symfony/symfony · GitHub
What is the point in PHP of using filter_sanitize_email if filter_validate_email checks if the email is valid? - Quora
FILTER_VALIDATE_EMAIL is not 100% RFC-conform · Issue #1923 · FriendsOfSymfony/FOSUserBundle · GitHub
![How to Validate (and Sanitize) User Input In PHP Using Filter_Input() and Filter_Var() | by John Morris | Medium How to Validate (and Sanitize) User Input In PHP Using Filter_Input() and Filter_Var() | by John Morris | Medium](https://miro.medium.com/max/1400/0*LOK4EwFmpQ_Ypn00.png)