UPDATE 10-15-23:
This is FIXED as of Lightroom Classic v13.0.1. You should be safe to update to Lightroom Classic v13.0.1.
Thanks @romanf
Yes, I can confirm there appears to be a bug in LrC v13.0 that is preventing changes from taking effect.
Users will need to downgrade to v12.5 or earlier until we can get this resolved. It is likely that Adobe will need to fix the bug with the SDK for this to work. This has happened once before and Adobe was super responsive in fixing it.
“How do I downgrade back to v12.5”
- Open the Adobe Creative Cloud app
- Make sure “Apps” is selected in the left pane
- Find the “Lightroom Classic” app, and click the “…” on the right side
- Select “Other Versions”
- Install v12.5
“How do I access my previous catalog?”
If you’ve already opened LrC v13, you might have updated your catalog to the new v13 format. The new catalog it made is not compatible with previous versions of LrC, so when you try to open the v13 format catalog with v12.5, it will probably throw an error…
The good news is that when Lightroom upgrades your catalog, it leaves your previous catalog untouched. So you should be able open Lightroom v12.5, then choose the catalog as it was named prior to when you ran the update.
You can learn more here.
“What versions of Negative Lab Pro does this impact?”
The bug in LrC v13.0 impacts all versions of Negative Lab Pro (and any plugin that is sending changes to Lightroom’s Tone Curve Panel).