sequences within the current group do not specify the substitution character.

Until RTF specification version 1.5 release in 1997, RTF only handled 7-bit characters directly and 8-bit characters encoded as hexadecimal (using \'xx). Since RTF 1.5, however, RTF control words generally accept signed 16-bit numbers as arguments. Unicode values greater than 32767 must be expressed as negative numbers. If a Unicode character is outside BMP, it is encoded with a surrogate pair. Support for