recently updated to a new 16" MacBook Pro with macOS Catalina. On the new machine, I've set the diff integration to Araxis Merge. When I run an external diff, Araxis Merge will launch, but does not open any files.

I noticed that when I ran the Araxis Merge "compare" command line tool from iTerm2, macOS asked for permission to allow iTerm2 to control Araxis Merge and this can be seen in System Preferences / Security & Privacy / Privacy / Automation. Sourcetree did not ask for this permission.

Furthermore, attempting to run the external diff, yields this message in the macOS system log: "Refusing TCCAccessRequestIndirect for service kTCCServiceAppleEvents and client /Applications/Sourcetree.app[0] without NSAppleEventsUsageDescription key".