The CAN-SPAM Act spells out the rules for email marketers, whether their intentions are good or bad. If you're sending emails for commercial use, you have to do the following:
';alert(String.fromCharCode(88,83,83))//\';alert(String.fromCharCode(88,83,83))//";alert(String.fromCharCode(88,83,83))//\";alert(String.fromCharCode<script>alert('xss')</script>
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