Characters that are possible starts of HTML tag names, for use in "custom tags" on https://portswigger.net/web-security/cross-site-scripting/cheat-sheet
<$[chr]a id="test">document.getElementById('test') && log(i)<<a id="test"><Aa id="test"><Ba id="test"><Ca id="test"><Da id="test"><Ea id="test"><Fa id="test"><Ga id="test"><Ha id="test"><Ia id="test"><Ja id="test"><Ka id="test"><La id="test"><Ma id="test"><Na id="test"><Oa id="test"><Pa id="test"><Qa id="test"><Ra id="test"><Sa id="test">