My Lightroom Classic was automatically upgraded to version 12.0.1. But after creating a new library for my collection of photo's the app was extremely slow on my MacBook Pro (Retina, Mid 2015) under Monterey 12.6. The app was not usuable anymore, because retrieving the info from the library for every item took more or less ten seconds. Also the developing data got extemely slow read, so that it took seconds before the picture was shown in its developed stage. It was not possible anymore to walk quickly through a collection. I removed the installation and downgraded to 11.4 after which the app was usuable again. I also set the update settings to manual instead of automatically.