I downloaded new Hub for Linux. I downloaded 2018.3.10b and added Mac OS X support. But I can’t build with this target. Building with script also throws the error. Same thing with 2019.1.0a9.
Look at contents of modules.json in Unity installation directory. A module with id “mac-mono” has wrong “destination” value: “{UNITY_PATH}”. Proper value is “{UNITY_PATH}/Editor/Data/PlaybackEngines/MacStandaloneSupport”.
You should to fix “destination”, and set “selected” to false to have ability to reinstall MacBuildSupport in proper way.
It’s in the folder where you installed Unity, or if you used Unity Hub, ~/Unity/Hub/Editor/{version}, where ~ is your home directory and {version} is the version of Unity you installed.
This just worked for me today, so it seems it’s still an issue.
Had to restart hub after making the change in modules.json then install mac support within hub.