How to Clear Private Data in Mozilla Firefox

It's easy to remove all or some of your browsing history

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Web browsers take great care to maintain your privacy. Still, you can take steps that 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, particularly if you use a public computer. If you do not clear your private data, the next person using the same computer might catch glimpses of your browsing session.

Clearing Your Firefox History

Firefox remembers a lot of information for you to make your browsing experience more pleasant and productive. This information is called your history, and it consists of several items:

  • Cookies store information about the websites you visit.
  • Browsing history is a list of sites you visited.
  • Download history is a list of the files you downloaded.
  • Form history contains information you entered into online forms.
  • Search history includes all the terms you entered into Firefox's search bar.
  • The Cache stores temporary files that Firefox downloads from the internet to speed up your browsing experience.
  • Offline Website Data consists of files a website stores on your computer that allow you to use it even when you aren't connected to the internet.
  • Site Preferences are site-specific preferences including permissions for a site such as a pop-up blocker exception
  • Active Logins occur when you log in at a website that uses HTTP authentication.

How to Clear Your Firefox History

Firefox redesigned its toolbar and features for 2018. Here's how you clear the history, including all or some of the items listed above:

  1. Click the Library button at the top right of the screen. It resembles books on a shelf.
  2. Click History > Clear Recent History.
  3. Select a time range that you want to clear by clicking the drop-down menu next to Time range to clear. Choices are Last Hour, Last Two Hours, Last Four Hours, Today, and Everything.
  4. Click the arrow next to Details and place a check in front of each of the history items that you want to clear. To clear them all at the same time, check them all.
  5. Click Clear Now.

How to Set Firefox to Automatically Clear the History

If you find yourself clearing the history frequently, you may prefer to set Firefox to do it for you automatically when you exit the browser. Here's how:

  1. Click the Menu button (three horizontal lines) in the far right corner at the top of the screen and select Preferences.
  2. Select Privacy & Security.
  3. In the History section, use the drop-down menu next to Firefox will to select Use custom settings for history
  4. Place a check in the box in front of Clear history when Firefox closes.
  5. Click the Settings button next to Clear history when Firefox closes and check the items you want Firefox to clear automatically each time you quit the browser.
  6. Click OK and close the preferences screen to save your changes.