I am using the Mac OS Contacts app version 9.0 (latest). I only have the option to "Look for duplicates..." which will then allow an auto-merge option if it finds duplicate. What it doesn't do is show me which entries will be merged.
Other Apple apps and the old contacts app allowed showing duplicates. This feature seems to have been removed in the last 3 (?) major Mac OS releases. Mac OS 10.6 had it.
How can I find out what will be merged before using the auto-merge option?