This vector shows what Named HTML entities that can be closed with !.
<img src=data: onerror="`&$[data1]!x`==`&$[data1];!x`?log('$[data1]'):0"><img src=data: onerror="`ã!x`==`ã!x`?alert('atilde'):0"><img src=data: onerror="`î!x`==`î!x`?alert('icirc'):0"><img src=data: onerror="`¼!x`==`¼!x`?alert('frac14'):0"><img src=data: onerror="`¾!x`==`¾!x`?alert('frac34'):0"><img src=data: onerror="`Û!x`==`Û!x`?alert('Ucirc'):0"><img src=data: onerror="`Ó!x`==`Ó!x`?alert('Oacute'):0"><img src=data: onerror="`ü!x`==`ü!x`?alert('uuml'):0"><img src=data: onerror="`ò!x`==`ò!x`?alert('ograve'):0"><img src=data: onerror="`ú!x`==`ú!x`?alert('uacute'):0"><img src=data: onerror="`Ð!x`==`Ð!x`?alert('ETH'):0"><img src=data: onerror="`<!x`==`<!x`?alert('lt'):0"><img src=data: onerror="`þ!x`==`þ!x`?alert('thorn'):0"><img src=data: onerror="`¥!x`==`¥!x`?alert('yen'):0"><img src=data: onerror="`´!x`==`´!x`?alert('acute'):0"><img src=data: onerror="`ä!x`==`ä!x`?alert('auml'):0"><img src=data: onerror="`¿!x`==`¿!x`?alert('iquest'):0"><img src=data: onerror="`Þ!x`==`Þ!x`?alert('THORN'):0"><img src=data: onerror="`Ý!x`==`Ý!x`?alert('Yacute'):0"><img src=data: onerror="`í!x`==`í!x`?alert('iacute'):0"><img src=data: onerror="`ª!x`==`ª!x`?alert('ordf'):0">