P: Doesn't Reopen Switching to Different Catalog

@johngjman@btinternet.com, you've posted in a thread that is almost certainly unrelated to your problem. Please start a new thread in the Discussions section, including more detailed description of what you see when you try to start LR.  Also do the LR menu command Help > System Info and copy/paste the entire contents in your post so we can see exactly which versions of hardware and software LR thinks you're running and important LR options that are set.

i've just updated to the new Oct release and now can not use Lightroom at all the app. will not stay open after optimizing to a new cat, have sent reports to both Apple and Adobe but no help so far and my dealines are looming fast !

It happens to me now perhaps 1/3 to 1/2 of the time. I've tried but failed to identify a recipe for reproducing it reliably across machines, making it less likely it will get attention from Adobe.  I've tried tracing internal errors using the -tracebacks switch but didn't learn anything (mainly because the problem didn't occur while I was tracing).

It strikes me personally because I have several test catalogs for plugin development and helping out on the forums, as well as two personal catalogs with much different purposes.   So I'm constantly switching catalogs, many times a day.  Not representative of the typical user.

Same thing happens to me every time. M1 MBP and M2 Mini running Ventura latest.

I see this happening regularly. It also happens when Optimize Catalog is used.

I've noticed this misbehavior a few times.  I've also noticed that the samizdat "restart" script:

import "AgApplication".relaunch ()

that many of us have used for years fails intermittently. 

But unless there is a precise recipe by which Adobe can reproduce these symptoms (or if dozens of people report it), the problem won't get addressed.