E0019: escaping '-' is not allowed in tag names; write '-' instead

JSX tag names and attributes can contain Unicode escape sequences starting with \u. It is a syntax error for a Unicode escape sequence to resolve to the - character (U+002D):

function Font() {
  return <svg:font\u{2d}face font\u002dfamily="Helvetica Standard" />;
}

To fix this error, write - instead of \u{2d} or \u002d:

function Font() {
  return <svg:font-face font-family="Helvetica Standard" />;
}

Introduced in quick-lint-js version 2.0.0.

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