Another W for Signal

Librewolf or debloating user.js?

Can only guess, but nixpkgs says the package provided is org.gnome.decibels not decibels. Maybe try this command

It is called pkgs.decibels. Should be feasible if you just did

  environment.gnome.excludePackages = [
    pkgs.decibels
  ];

Ubuntu -> Mint -> Arch -> NixOS

Ubuntu really drove me away for some time. Only when I got to Mint, I felt that Linux could be a daily driver. Arch made me strangely reinstall it every few days. Not by not working but by having the feeling of dirtying the machine on use.

NixOS is really what I want to use the rest of my life. Very complicated on first use but definitly worth it (for me).

Most scam apps are in the Google Play Store btw

I thought it was okay with the licensing to sell copies of GPL licensed software as long as the customer had the option to get the source code.

yourdevice.ch has some services.