Log in on each browser you use and one press of Fuzz or Test fuzz runs the vector in all of them, with every browser's results side by side.
This vector shows what characters are allowed in-between hyphens of a HTML comment.
Unable to render tweet button
<!-$[chr]- ><xmp>--><img src/onerror=log($[i])>-->
<!--- ><xmp>--><img src/onerror=alert(45)>-->
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