...Spoofchecking and DNSCheckValidation validation requires that your PHP system has the PHP Internationalization Libraries (also known as PHP Intl). PHP version upgrades will happen to accomodate to the pace of major frameworks. Minor versions bumps will go via minor versions of this library (i.e: PHP7.3 -> v3.x+1). Major versions will go with major versions of the library. EmailValidatorrequires you to decide which (or combination of them) validation/s strategy/ies you'd like to follow for each validation. Note that warnings are deviations from the RFC that in a broader interpretation are acceptded. ...