It is important to note that you have the --> at the end, so the string inside the comment cannot end with - or else you will have --->

s/(?<=<!--)(.*?)-->/($_=$1);s|--|-¬|g;s|-$|¬|;"$_-->"/seg
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use this to test it and see what it is matching:

s/(?<=<!--)(.*?)-->/($_=$1);s|--|-¬|g;s|-$|¬|;"[$_]-->"/seg
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