<!-- Begin "Business Email Validation" || Help center -->
<!-- Insert in Settings->Javascript->Footer -->
<!-- CS:20200722-02-0 -->
<script>
  var label = 'Email';
  var standardEmail = /^(?!.+@(gmail|google|yahoo|outlook|hotmail|msn)\..+)(.+@.+\..+)$/; 
  var errorMessage = 'field: Please enter your business email address.';
  
  document.querySelector("input[name='" + label + "']").addEventListener("input", function(e){
    e.target.value = e.target.value.toLowerCase();
  });   

window.__custom_form_validations = [
    {
      fieldName: label,
      validationFn: function (input) {
        return {
          isValid: standardEmail.test(input.value),
          message: window._Translate.get(errorMessage),
        };
      },
    },
  ];
</script>
<!-- END code that excludes standard email domains -->