Numbers duplicate aliases in an OTO up to a maximum number, and deletes the rest. Works for Windows (oto.ini) and Mac (oto_ini.txt).
Download and run "Number Duplicate Aliases.jar" to use. (You can set the maximum to 0 to delete all duplicates). Make sure the OTO you want to edit is in the same folder as the jar. On Windows, you may have to convert the oto to UTF-8.