Ok, in 2021 it’s really not the latest version of Adobe but it still servers it’s purpose. At least it did until yesterday. After switching to „persons“ it crashed. Worse, it did not start-up again and kept crashing. There were lot’s of suggestions on the web, mostly about clearing the cache. What had helped at then end was much more simple: Reset Lightroom to the defaults by pressing OPT+SHIFT while starting the app.