Xcode 11.4 will be released shortly, the App Store requirements mandate iOS 13 soon and COVID-19 along with some planned but cancelled vacation made me finally upgrade to Catalina. The installation itself went smooth and the occasional hiccup was expected.
After switching to zsh, some of my command line tools didn’t work anymore. That was fixed quickly, but unfortunately, Lightroom 6.x isn’t working properly anymore. It beachballs for a while and SIGSEGVs when quitting. I am not sure if it is worth spending a lot of time trying to research the cause. For now, I will keep fingers crossed that it does not corrupt the catalog and ignore the crash.