you need to find the mail() part in the script
it'll look like this:
mail ('targetmail', 'subject', 'content', 'additional_headers');
you can directly add another address in targetmail by using comma:
mail ('you@domain.com,anotheryou@domain.com', 'subject',...
if the targetmail is a variable, you might be able to slip it in like this:
mail ($targetmail . ',anotheryou@domain.com', subject,....
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