@dev by the specs, which drives the browser parser
Boolean properties are true when present, false when absent. They are also false when present with empty string. If they are true and should be XML valid they have the value of the name of the property as string.
`<input disabled=“disabled”> //false`
Data are always string, not a Bool, so when used needs to have a value, otherwise it will be “falsy” to JS (empty string)