- Open Day One.
- Go to Preferences > Sync.
- Click the folder icon in the "Data File" section. My folder is called "Journal_dayone."
- A Finder window will open. Keep it open and close Day One.
- Drag the "entries" folder to Sublime or another text editor with folder support.
- Find and replace. Make sure it's case-sensitive if necessary.
- Open Day One to check.