If you are searching how to log out of messages on mac, open the Messages app on your Mac and select Messages > Settings from the menu bar. Click the iMessage tab, then select Sign Out and confirm. Apple states that signing out of iMessage stops Messages from receiving iMessages on that Mac. This is useful if you are using a shared Mac, switching Apple Accounts, or simply do not want your messages appearing on the computer. DataRecovee also provides a guide covering how to sign out of iMessage on a Mac.
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