Undefined Character (U+FFFFF)

Block:	Supplementary Private Use Area-A, U+F0000 - U+FFFFF^[1]
Plane:	Supplementary Private Use Area planes, U+F0000 - U+FFFFF^[1]
HTML Entity:	`󿿿` `󿿿`
UTF-8 Encoding:	`0xF3 0xBF 0xBF 0xBF`
UTF-16 Encoding:	`0xDBBF 0xDFFF`
UTF-32 Encoding:	`0x000FFFFF`

References