Stabilized Technical Report

UTS #22, "Unicode Character Mapping Markup Language" has been stabilized: There are no plans to ever publish another update for it. The last version can be found at https://www.unicode.org/reports/tr22/tr22-8.html.

The discussion of issues in UTS #22 remains relevant, although the specific XML format is not commonly used. For example, the Unicode ICU project uses conversion data files in a different format, as does the W3C Encoding specification.

In addition, newer resources such as UTR #36, Unicode Security Considerations, the Unicode Standard Section 3.9, Unicode Encoding Forms (especially definition D93 Encoding form conversion), and the Unicode Standard Section 5.22, Best Practice for U+FFFD Substitution, expand on many of the issues discussed here.

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