Many web browsers offer some type of private mode so that you can cover your tracks throughout a browsing session. In Mozilla Firefox, Private Browsing can be activated at any time and in a few different ways.
Private Browsing doesn't mean your activities on the web are entirely anonymous. Your ISP or employer can monitor which sites you visit, and some of your actions on those sites. Website owners may collect some information like your IP address and general location.
Open a New Private Browsing Window
When you use this method, all tabs in the window will be private.
Select the hamburger menu in the upper-right corner of the browser window.
Select New Private Window.
You can use keyboard shortcuts instead of this menu option. In Linux or Windows, press Control+Shift+P. In macOS, press Command+Shift+P.
A new browser window appears, indicating you're using Private Browsing mode and detailing what that means. All tabs opened in this new window are private, as indicated by the purple and white eye mask icon located on the left side of the title bar.
Open a Link in Private Browsing Mode
The right-click menu takes you to a private window.
To open a link from a web page in Private Browsing mode, right-click the link to display a context menu. On macOS, press the Control key and right-click the link.
Select Open Link in New Private Window.
The link's destination page should 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.
Automatically Use Private Browsing in Firefox
You can also configure Firefox so that every session is essentially private, although not technically in Private Browsing mode.
Go to the Firefox address bar, enter about: preferences, then press Enter.
In the Firefox General preferences, select Privacy & Security.
Scroll down to the History section, then select the Firefox will drop-down menu and choose Never remember history.
A pop-up window prompts you to restart the browser to enable this feature. Select Restart Firefox now.
Although the purple and white Private Browsing mask may not be displayed, Firefox doesn't retain history and other browsing-related data as long as this setting is enabled.
What Data Is Not Stored While in Private Browsing Mode?
Firefox stores quite a bit of information on your computer during a browsing session. With Private Browsing mode active, a lot of this data is either never saved locally or automatically erased when you close a private tab or window. This can be 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 historyBrowsing historyCacheCookies Web form information Search bar keywordsSaved passwords
In Private Browsing mode, the bookmarks you create are stored and are available the next time you launch Firefox. Additionally, any downloaded files remain on your computer unless you manually delete those files.