L2/20-054 Title: Proposal to merge three Identifier_Types in UTS #39 Author: Roozbeh Pournader (WhatsApp) Date: 2020-01-15 UTS #39 defines three different property values for Identifier_Type that are neither well-defined nor followed properly in their assignments to characters. On top of that, the text for version 13.0 of UTS #39 includes: "For the qualifiers on usage, Obsolete, Uncommon_Use and Technical, the distinctions among the Identifier_Type values is not strict and only one might be given." The author recently tried to determine the best property values for a few characters new to Unicode 13.0, and had a hard time drawing the line between these for some characters. Since there is no practical distinction among the three property values for any algorithm defined by the Unicode Consortium, the author suggests merging the two property values "Obsolete" and "Technical" into "Uncommon_Use". The definition of "Uncommon_Use" can be expanded to include the definitions of the other two property values.