I'm trying to edit GH5 HLG/HVEV video in FCPX 10.4.8 on OSX Catalina 10.15.5. This is a new computer and I could have sworn that I was able to see and edit that codec in my old Mac. Also, when I export prores 422 with other footage, for some reason I can't playback that output in Quicktime. I tried seeing if I had the proapps codecs installed and googled a bit last night, but couldn't find what I had done wrong... Any ideas?
Thanks for the info. I checked the Pro Video Formats (was OK), reset all my preferences, cleaned up all render files using Final Cut Pro Library Manager, and re-imported using "optimise media" and that seemed to fix things.