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.
Characters that are may be part of HTML tag names. These are less strict that the first character
Unable to render tweet button
<a$[chr] id="test">
document.getElementById('test').tagName.length > 1 && log(i)
<a0x0B id="test">