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 checks for what characters are allowed before the greater than character.
Unable to render tweet button
<!----$[chr]><found>
<!----!><img/src/onerror=alert(1)>
<!-----><img/src/onerror=alert(1)>
<!---->><img/src/onerror=alert(1)>
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