Apple macOS 10.15 (Catalina) is supported
Apple macOS 10.14 (Mojave) is supported
Items (features and-or functionality) are marked as deprecated when a more current, and usually enhanced, alternative is available.
Whilst the deprecated item will remain usable, it is no longer supported, will a be removed in a future release. You should plan to move to an alternative, supported, solution as soon as practical.