First it added something called ublock origin which I did not ask for.

The Firefox web browser from mozilla.org does not come with Extensions like uBlock Origin as it is a third-party extension. https://addons.mozilla.org/firefox/addon/ublock-origin/

https://support.mozilla.org/en-US/kb/cannot-remove-add-on-extension-or-theme

Private mode windows just establishes a private window for that tab, but I can find nothing in Settings which will do so universally. This time when I opened Firefox it automatically installed AdBlock. It now looks like I have both AdBlock and Privacy Badger installed, neither of which I asked for. Firefox is suddenly installing these things automatically, and I do not want ANY of them. This looks more and more like I Firefox bug. I have used Firefox since 2007 and have never had this problem.

If you type or paste about:policies in the address bar and press Enter to load that page, are there any add-on related policies listed on the Active panel? Normally, it just says "The Enterprise Policies service is inactive." so anything else could be an indication that someone has embedded a policy file in your Firefox (or policies in the Windows registry).