I discovered ART [0] from other comments here, and it looks like it explicitly supports Digikam/Darktable metadata sync through XMP files: > Better metadata ha

I discovered ART [0] from other comments here, and it looks like it explicitly supports Digikam/Darktable metadata sync through XMP files: > Better metadata handling (thanks to the exiv2 and exiftool libraries), with (optional) support for reading and writing XMP sidecar files. I will check it out soon, ART has some very useful features that I miss from Darktable in RawTherapee. [0] https://bitbucket.org/agriggio/art https://bitbucket.org/agriggio/art