{ pkgs, ... }: { systemd.user.services.firefox-daemon = { Unit = { Description = "Pre-load Firefox in background for fast startup"; After = [ "graphical-session.target" ]; }; Service = { Type = "simple"; ExecStart = "${pkgs.firefox}/bin/firefox --headless"; Restart = "on-failure"; TimeoutStartSec = "5"; }; Install = { WantedBy = [ "graphical-session.target" ]; }; }; }