How to Clear Private Data in Mozilla Firefox

Tips on How to Empty Caches and Remove Cookies

Shadow of businessman spying on colleague using computer
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For Better Web-Based Email Security

Web-based email services take great care to make sure only you can see your messages. You may have to enter a password every time you check your mail, for example, and get logged out automatically after some time.

Still, you can also contribute to your security. It is prudent to empty your browser's cache of web pages and stored passwords as well as clear the browsing history or cookies, for example, if you use a web-based email service from a public computer.

If you do not clear your private data, the next person using the same computer could get a chance to catch glimpses of your emails or even your password.​

Clear Private Data, Empty Caches and Remove Cookies in Mozilla Firefox

To delete personal cookies, browsing history, cached web pages, saved forms or passwords and other personal data after accessing a web-based email service using Mozilla Firefox:

  • Select Tools | Clear Private Data... from the menu.
  • Make sure Browsing History, Saved Form and Search History, Cache, Cookies, Saved Passwords and Authenticated Sessions are checked.
  • Click Clear Private Data Now.
  • Close Mozilla Firefox.

Clear Private Data Automatically When You Exit Mozilla Firefox

For automatic protection, Mozilla Firefox can void your private data every time you close it. If you are sure that browsing history, saved passwords or a cache are of no value to you, this can be very useful.

(You can choose what kind of data is automatically deleted, too.)

  • Select Tools | Options... (or Firefox | Preferences...) from the menu in Mozilla Firefox.
  • Go to the Privacy tab.
  • Make sure Always clear my private data when I close Firefox is checked.
  • Click Settings....
  • Choose the desired data to be erased.
  • Click OK.
  • Close the configuration dialog.