When I start the cloned app-vm it naturally starts as disposable with all the above mentioned convenient Firefox ingredients: Now this sounds to good to be true: I have a convenient firefox as I want it to be, and the whole thing is self-destructive after shutdown. My question is now, if there would be any security issue in this configuration. If this would be a fairly secure working solution then it would make the whole configuration with arkenfox user.js, Autoconfig and policies.json look obsolete.