Open Firefox
Type about:config in address bar
Press Enter
Type browser.privatebrowsing.autostart in Search:
Right click browser.privatebrowsing.autostart and click Toggle (value will change to True)
Restart Firefox to apply settings
Alternate method
Click Menu
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Click Options
Click Privacy
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Click Drop Down Box next to Firefox will:
Choose Use custom settings for history
Select checkbox Always use private browsing mode
Click OK to restart FirefoxType about:config in address bar
Press Enter
Type browser.privatebrowsing.autostart in Search:
Right click browser.privatebrowsing.autostart and click Toggle (value will change to True)
Restart Firefox to apply settings
Alternate method
Click Menu
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Click Options
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Click Privacy
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Click Drop Down Box next to Firefox will:
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Choose Use custom settings for history
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Select checkbox Always use private browsing mode
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