"autofocus" is boolean attribute, so it should has no value, or autofocus="autofocus"
2.5.2 Boolean attributes ... If the attribute is present, its value must either be the empty string or a value that is an ASCII case-insensitive match for the attribute's canonical name, with no leading or trailing whitespace. Note: The values "true" and "false" are not allowed on boolean attributes. To represent a false value, the attribute has to be omitted altogether.