Some Chinese characters (Hanzi) can't display on many (or all) Chinese operating system. like some Hanzi on unicode Supplementary Ideographic Plane .
see http://en.wikipedia.org/wiki/Supplementary_Multilingual_Plane#Supplementary_Ideographic_Plane
http://en.wikipedia.org/wiki/Han_unification
http://en.wikipedia.org/wiki/CJK_Unified_Ideographs
http://zh.wikipedia.org/wiki/Wikipedia:Unicode%E6%89%A9%E5%B1%95%E6%B1%89%E5%AD%97
http://zh.wikipedia.org/wiki/Template:CJK-New-Char
Version: unspecified
Severity: enhancement
See Also:
T65122: improve detectTofu algorithm so it can detect replacement characters in fixed-width glyphs