macos – Move Secure Notes items from keychain from one Mac to another?

A keychain has been created to hold a large number of Secure Notes elements. These are do not in the default keychain files created by Apple.

In previous versions of macOS, I could simply drag the keychain file from a Mac to a new Mac. Now, in macOS Mojave, it does not work. When I drag the my_own_keychain.keychain-db from my personal folder> Library> Keychain on the old Mac and place it in the same place on the new Mac, Keychains application fails to recognize it.

How can I move my own keychain file from an older Mac to a new Mac?