How to config Firefox for Private Browsing?

How to Start a Private Browsing Session in Firefox

You can activate Private Browsing mode in a few different ways.

Open a new Private Browsing window

  1. Select the Hamburger menu in the upper right-hand corner of the browser window.
  2. Select New Private Window.
  3. A new browser window will now appear, indicating you’re in Private Browsing mode and detailing what that means. All tabs opened within this new window will be private, as indicated by the purple and white “eye mask” icon on the far left-hand side of each tab’s title bar.

screenshot of Firefox for Windows 10

screenshot of Firefox menu on Windows 10

[infobox] You can also use the following keyboard shortcuts in lieu of this menu option. Linux or Windows: Control+Shift+P; macOS: Command+Shift+P[/infobox]

  1. To open a link from a web page in Private Browsing mode, first right-click the link so Firefox’s context menu appears. On macOS, press the Control key and right-click the link.
  2. Select either Open Link in New Tab or Open Link in New Private Window.
  3. The link’s destination page should now be visible in a private tab or window, depending on your selection. Check for the purple and white mask in the page’s title bar to ensure you're in Private mode.

How to Automatically Use Private Browsing in Firefox

You can also choose to configure Firefox so every session is essentially private, although not technically in Private Browsing mode.

  1. Type about: preferences in Firefox’s address bar, then press Enter or Return.
  2. Firefox’s General preferences interface should now be displayed. Select Privacy & Security.
  3. Scroll down to the History section, then select the Firefox will drop-down menu and select Never remember history.
  4. A pop-up window will now appear, informing you that the browser must be restarted to enable this feature. Select Restart Firefox now.
  5. Although the purple and white Private Browsing mask may not be displayed, Firefox will not retain history and most other browsing-related data as long as this setting is enabled.

screenshot of Firefox preferences

screenshot of Firefox History preferences

screenshot of Restart Firefox dialog

What Data is Not Stored While in Private Browsing Mode?

Firefox stores quite a bit of information on your hard drive over the course of a typical browsing session. With Private Browsing mode active, a lot of this data is either never saved locally or automatically erased once you close a private tab or window. This can be especially useful when accessing the internet on a shared computer.

The following data is not left behind at the end of a Firefox Private Browsing session:

  • Download History
  • Browsing History
  • Cache
  • Cookies
  • Web Form Information
  • Search Bar Keywords
  • Saved Passwords

[infobox]In Private Browsing mode, any Bookmarks you create are stored and will be available the next time Firefox is launched. Additionally, any files you’ve chosen to download remain on your hard drive unless you choose to manually delete them. [/infobox]