How to Delete a Username on a Facebook Login on a Mac

All Apple computers running the Mac OS X operating system come with the Safari web browser installed on them. When you log in to a Facebook account on your Mac, Safari stores a record of your username in a special data file known as a cookie. If you do not want your Mac to remember your username when you visit the Facebook website, you can manually delete the Facebook cookies in Safari.

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You can control what cookies Safari stores on your Mac computer.

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Click on the "Safari" icon in the dock to launch the web browser.

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Open the "Safari" menu at the top of the screen and choose "Preferences."

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Go to the "Security" tab at the top of the pop-up window.

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Click on the button labeled "Show Cookies." A new window will open with a list of all the cookie files stored in your web browser.

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Type "facebook" into the search field at the top of the window to view only the cookies related to the Facebook website.

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Highlight all of the cookies with "facebook.com" listed in the "Website" field. You can highlight multiple cookies by holding down the "shift" key and clicking on each one.

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Press the "Remove" button to delete the highlighted cookies.

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Press "Done" to return to the "Preferences" window. Now when you visit the Facebook website, your Mac will no longer remember your username.