The Unicode Standard version 14.0.0 is tentatively scheduled for September 2021. As per usual, since the .NET runtime carries a copy of Unicode-derived data, we should update our data files to match version 14.0.0 when it's released.

This will affect the following APIs:

• System.Globalization.StringInfo
• System.Globalization.CharUnicodeInfo
• System.Text.Encodings.Web.*
• System.Text.Json.* (since it depends on System.Text.Encodings.Web)

For instructions on how to update the runtime-carried Unicode data files, consult the GenUnicodeProp docs and the STEW docs. Also update the UnicodeUcdVersion data throughout our .csproj files (see samples).

See #2378 for the changes we made for Unicode 13.0.0 in .NET 5.

We should also keep an eye out for any changes to UAX#29 that might be part of the Unicode 14.0.0 wave. Our tools will automatically pick up any changes to a code point's Grapheme_Cluster_Break property, but if the algorithm in Sec. 3.1.1 changes as part of Unicode 14.0.0 then we may need to update the logic in TextSegmentationUtility.cs.