Since Yosemite the only way to add custom ringtones was to drop them into:
Is this location still our only option for adding custom ringtones to macOS or is there a new ~/Library/ location available to users?
I've had no luck isolating anything within
~/Library that indicates that it is a ringtone storage location for Messages.app, etc.
Additionally, there is also an
AlertTones folder in the above parent folder location:
It appears that both of these will likely have to be remapped to something like