@cavitee
Using commas to separate multiple sites did not work for me. However, this format worked:
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.5.0/jquery.min.js"></script>
<script>
$(document).ready(function() {
$('[href*="amazon.com"]').attr('rel','sponsored');
$('[href*="ebay.com"]').attr('rel','sponsored');
});
</script>
I hope this is correct, @tuanphan!