I upgraded directly from High Sierra to Catalina without any major issues, once I switched to a compatible GPU. Photoshop 2020 (v21.0.1) and the new Lightroom Classic v9.0 (Camera Raw v12) became unstable and jerky with High Sierra and the GeForce 1060 GPU with the last Adobe update. I replaced...
iPatch's Build: i7-2700K - GA-Z68XP-UD4 - 16GB RAM - Radeon 6850 - SSD 256 GB
All parts are from Sofmap in Japan, they can also be found at other shops at http://kakaku.com (Japanese only)
OS Lion 10.7.2 clean install (Japanese)
CPU Core i7 2700K