I tried to develop my own project index for some time https://villalba.studio/project-index/ (which was probably a bit clunky and unreliable) and then suddenly! Boom. The option just appeared on Laytheme a few weeks ago!
Thank you guys! I'm very happy with the new feature BUT I encountered the follwoing problem: A few tags don't display in the actual list (the project index is at the bootom of this page https://villalba.studio/info/)