Once everything has been changed, close, and restart Firefox to effect the changes. You can select Never remember history as well from the drop-down menu, and you will always be in Incognito mode. This will set the Firefox browser in private browsing forever. Here are the steps to set Firefox private browsing mode always: You can technically browse in incognito mode forever if you change this setting in your Firefox Privacy Options. Mozilla Firefox is set to remember history by default. If the purple cover exists, you are browsing in Private browsing mode.
If you want to know whether you are using Incognito Mode on Mozilla Firefox or not, just check the window you are using for a purple mask at the top.
