Catalog images not loading

Thanks everyone who took time to read this but appears to have spontaneously resolved. Still unsure what was happenin

Not a MACOS user any longer, so a bit out of the loop. And I am very sure this reply would be different for Windows OS.

When you are done for the day, do you leave your MAC on, or perhaps turn it off? And if you turn it off, do you perhaps unplug it (laptop for example)

If I understand it correctly, a Restart on a MAC will not clear out everything that may be going wrong (opposite of Windows)

If I understand it correctly, Shutting Down a MAC may clear out everything, but also unplugging it as to eliminate power will defiantly flush out everything that may be going wrong (in memory, in CACHE, etc)

So was the resolution perhaps due to a change in end of the day treatment of the MAC?

Can another member more savvy with MACOS provide insight?

Note, on Windows OS, unless you change a default setting for Fast Startup, a Shutdown leaves info for the Kernel in play, etc. while a Reset flushes it  all out, so trying to fix issues via a Shutdown may not work but a Restart may (if yo get a Kernel Panic, try that)

I have also had the same problem. Looking for a solution.

Lightroom also becomes non-responsive and crashes whenever I view "Catalog Settings" or attempt to switch to a previous catalog version.

Unfortunately that hasn't resolved the issue. 

Have you considered resetting the preferences file. Carefully read:

https://www.lightroomqueen.com/how-do-i-reset-lightrooms-preferences/

Your screen captures just scream loudly corrupt preferences file.