Step 3: Some websites use trackers that can monitor your activity across the Internet. Step 2: You can recognize that you in a private browsing mode by the mask located at the top right of the window. You can also use the Firefox private browsing incognito keyboard shortcut CTRL + SHIFT + P to open Private windows instantly. Pop-up windows will open with a couple of options, from there select the New Private Windows option. Step 1: Open the Firefox and at the right top corner, click on the hamburger icon to open Firefox menu. Also See: How to Use WhatsApp on Desktop Computer Using Chrome Browser How to do Use Private Browsing Mode in Mozilla Firefox To enable the Firefox strict protection list, follow the following steps.