It worked with private browsing before, thus making us deactivate it is NO solution. Users who use private browsing have theyr reason and will not deactivate it thus just switch to an adblocker who is not forcing them to turn it off!

Used it for years but since I went onto Kubuntu 22.04 (which maybe just a coincidence) it does not remember any filter list anymore. Not my own, not the language filter lists nor the filter lists that came with ABP. I select the filter lists, I make own filter lists and as soon as the browser is being restarted everything is gone! And there I was wondering why ads are not being blocked. (FF 100.0.2, 64-bit, Snap for Ubuntu canonical-002-1.0)

I have also tested the suggestion about the FF privacy settings who are mentioned below in German. It makes no difference. No ads are blocked, no filters being remembered. This time when I reinstalled ABP the filters where active from the start, after I restarted FF all filters where gone again including the one filter I have created by myself for testing purposes. Also those filters didnt take even when they where active and ads where shown everywhere I went.

Then I have tried another adblock addon and with that blocking works again so it is definetly ABP.