Hello, for other testing purpose, i’ve install the last beta of Catalina, last OSX from Apple, on a dedicated partition. The good news is Rack 0.6c and public dev beta of Rack V1.0 works ( but be really careful with this update, a lot of appz (all 32bits but not only) will not work) and it’s really buggy.
Just to let you know. 
Now will try to test sidecar feature ( ipad as second monitor…) rack on a touch screen ?