XProductAddOriginalIdentityUsingGroupNumberSuffix Property MSBuild Extension Pack Help 4.0.12.0
Copies original Identity metadata to result item as well - suffixed by the group number, i.e. you can use %(ResultList.Identity1).

Namespace: MSBuild.ExtensionPack.Framework
Assembly: MSBuild.ExtensionPack (in MSBuild.ExtensionPack.dll) Version: 4.0.0.0
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