InPrivate Browsing
Ive seen that others have also asked what I am about to and have gotten no response but I'm "THAT" mom that wont stop until I get a solution.... That being said my question / concern is: How do parents DISABLE "InPrivate Browsing". Seems awfully disturbing to me that there is no parental control that allows parents to remove that option to protect our children and I will not stop asking questions, emailing and calling if I can find a phone number, until I find resolution to know I can safely allow my children to use the internet without them being able to be sneaky and hide things that could potentially be a danger to their safety.... Obviously I am not the only parent concerned with this matter by the other questions Ive seen on this topic so all I can say is "do better Firefox", parents shouldn't have to struggle and not get responses on how to keep our children safe while using your browser
Opaite Mbohovái (2)
You can create a document called a Policy to disable private browsing but that may be more than you are able and willing to do. I'll provide a link if you wish to do that. In the meantime, the article linked below may explain it.
Otherwise, there may be security software which imposes parental controls.
https://support.mozilla.org/en-US/kb/customizing-firefox-using-group-policy-windows
See also DisablePrivateBrowsing: