Catalina disaster

At lisbon4, my signature will display some of the specs of my iMac mid 2015 with 27” 5K monitor with a 2GB GPU unit.

I was using LrC 9.x with Catalina just fine and upgraded to LrC when LrC 10.0 was released and all was fine. Of note here is Adobe updated the specs requirements for GPU.

Couple of weeks after the Lightroom upgrade Apple Big Sur was released and I upgraded my system. All was fine with LrC 10. Even though my GPU did not meet the “recommend spec” for 27” 5K monitors.

However when I updated to LrC 10.1, I started to get many performance problems in the Develop module. This continued into v 10.1.1 after struggling for a week I eventually reverted LrC 10.0 and things are fine.

You have not specified the specs about your Mac but you could try using the Adobe Creative Cloud app to uninstall LrC 10.1.1 and reinstall LrC 10.0.

There is nothing per se wrong with these applications in Catalina. Something is amiss on your machine so you need to figure out what's the conflict and where.

Did you delete the preferences from both first? 

If that doesn't work, try booting into Safe Mode and see if they crash (restart, hold down Shift Key). 

You should continue troubleshooting to identify the real cause, because many people — including myself right now — have been using Lightroom Classic and Photoshop in Catalina for many months, and they crash very very rarely for me. Therefore I do not think the cause is Catalina itself. The crashes might be tied to specific hardware, or specific software that’s also installed. For example, I would take a look at Mac third-party system extensions that are installed, in case one got brought forward that is not Catalina compatible.

I am not upgrading this Mac to Big Sur just yet. There are still some outstanding known issues, at least with Photoshop: Photoshop known issues in Big Sur

In addition I should have stated that I am using adobe CC, have the most recent versions of LR and PS loaded.