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 uses the query property to detect if the character is a question mark
Unable to render tweet button
<a href="https://example.com$[chr]foo" id=x></a>
document.getElementById('x').search.includes('foo') && log($[i])
<a href="https://example.com?foo" id=x></a>
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