Duplicate items can occur in the Types, Aircraft, Places, and People tabs, but they can easily be merged with the original item without losing any of the flight data associated with them.
Select the desired tab (i.e. People, or Types)
Select one, hold the
commandkey and select the others
Select "Logbook" from the app menu at the top of the screen
Select "Combine Selected Entries"
Read the message that pops up and make sure you understand that the items will be combined. This cannot be undone.
Note: You may need to run the Repair Logbook File tool under the Help menu to help complete and view the merge.
Open LogTen on your Mac and click "Help" then "Repair Logbook File" in the toolbar at the very top of your screen.