As a developer of genealogy applications that import GEDCOM files, I often find myself adding support for useful vendor specific GEDCOM tags. Do you have any favorites you’d like to see supported generally? I’ll go first. Location names are duplicated (with various spellings) often many times. @rootsmagic and legacytreegenealogists both support Location records that can be referenced from any event, and both support coordinates. Next I’d like to see fields for both archaic and modern names.