{
  pkgs,
  config,
  lib,
  ...
}:
let
  inherit (config.grimmShared)
    enable
    firefox
    locale
    sway
    ;
  inherit (lib)
    mkIf
    optionals
    mapAttrs
    optionalAttrs
    ;
in
{
  config = mkIf (enable && firefox.enable) {
    environment.systemPackages =
      [ ]
      ++ optionals config.services.desktopManager.plasma6.enable [ pkgs.plasma-browser-integration ];

    programs.firefox = {
      package = pkgs.firefox.override {
        extraPrefsFiles = [
          "${pkgs.arkenfox-userjs}/user.cfg"

          (pkgs.writeText "arkenfox-userjs-overrides.cfg" # javascript
            ''
              /// arkenfox user.js overrides.
              // We want session restore to work, for that we need to save history:
              // https://github.com/arkenfox/user.js/issues/1080#issue-774750296
              lockPref("privacy.clearOnShutdown.history", false);
              lockPref("privacy.clearOnShutdown_v2.historyFormDataAndDownloads", false);
              lockPref("privacy.clearOnShutdown.offlineApps", false); // Site Data
              lockPref("privacy.clearOnShutdown_v2.cookiesAndStorage", false); // Cookies, Site Data, Active Logins [FF128+]
            ''
          )
        ];
      };
      enable = true;
      languagePacks = optionals locale [
        "de"
        "en-US"
      ];
      policies = {
        ExtensionSettings =
          # (mkIf firefox.disableUserPlugins { "*".installation_mode = "blocked"; }) //
          (
            mapAttrs (guid: shortId: {
              # explicit plugins by config
              install_url = "https://addons.mozilla.org/en-US/firefox/downloads/latest/${shortId}/latest.xpi";
              installation_mode = "force_installed";
            }) config.grimmShared.firefox.plugins
          );
        DisableTelemetry = true;
        DisableFirefoxStudies = true;
        EnableTrackingProtection = {
          Value = true;
          Locked = true;
          Cryptomining = true;
          Fingerprinting = true;
        };
        DisablePocket = true;
        DisableFirefoxAccounts = true;
        DisableAccounts = true;
        DisableFirefoxScreenshots = true;
        OverrideFirstRunPage = "";
        OverridePostUpdatePage = "";
        DontCheckDefaultBrowser = true;

      FirefoxHome = {
        TopSites = true;
        SponsoredTopSites = false;

        Pocket = false;
        Snippets = false;
        Highlights = false;
        Locked = true;
      };

      FirefoxSuggest = {
        WebSuggestions = false;
        SponsoredSuggestions = false;
        ImproveSuggest = false;
        Locked = true;
      };

      SearchEngines = {
         Default = "SearXNG";
         Remove = ["Bing" "Amazon.ca" "eBay"];
         Add = [
           {
             Name = "SearXNG";
             URLTemplate = "http://search.grimmauld.de/search?q={searchTerms}&safesearch=1&categories=general";
             IconURL = "https://raw.githubusercontent.com/searxng/searxng/refs/heads/master/searx/static/themes/simple/img/favicon.svg";
             Alias = "searx";
           }
           {
             Name = "Nix Package Search";
             URLTemplate = "https://search.nixos.org/packages?channel=unstable&query={searchTerms}";
             IconURL = "https://github.com/NixOS/nixos-artwork/raw/refs/heads/master/logo/nix-snowflake-white.svg";
             Alias = "np";
           }
           {
             Name = "NixOS Option Search";
             URLTemplate = "https://search.nixos.org/options?channel=unstable&query={searchTerms}";
             IconURL = "https://github.com/NixOS/nixos-artwork/raw/refs/heads/master/logo/nix-snowflake-white.svg";
             Alias = "no";
           }
           {
             Name = "NixOS Wiki";
             URLTemplate = "https://nixos.wiki/index.php?search={searchTerms}";
             IconURL = "https://github.com/NixOS/nixos-artwork/raw/refs/heads/master/logo/nix-snowflake-white.svg";
             Alias = "nw";
           }
           {
             Name = "Home Manager Option Search";
             URLTemplate = "https://mipmip.github.io/home-manager-option-search?query={searchTerms}";
             IconURL = "https://github.com/NixOS/nixos-artwork/raw/refs/heads/master/logo/nix-snowflake-white.svg";
             Alias = "hm";
           }
         ];
       };
        
        Preferences = {
          "pdfjs.enableScripting" = false;
          "signon.rememberSignons" = false;

          "media.hardware-video-decoding.enabled" = true;
          "media.ffmpeg.vaapi.enabled" = true;
          "media.rdd-ffmpeg.enabled" = true;
          "media.navigator.mediadatadecoder_vpx_enabled" = true;
          "media.eme.enabled" = true;
          # "media.peerconnection.enabled" = false;
          
          "browser.startup.homepage" = "about:home";
          "browser.startup.page" = 1;
          "browser.newtabpage.enabled" = true;
          "browser.toolbars.bookmarks.visibility" = "newtab";
          "browser.download.useDownloadDir" = true;

          # "general.useragent.override" = "";
          # "permissions.memory_only" = true;
          "privacy.resistFingerprinting" = true;
          "privacy.resistFingerprinting.block_mozAddonManager" = true;
          "network.http.referer.XOriginPolicy" = 1;
          "network.http.referer.XOriginTrimmingPolicy" = 1;
          "network.http.sendRefererHeader" = 0;

          "network.proxy.socks" = builtins.head (builtins.split ":" config.services.tor.torsocks.server);
          "network.proxy.socks_port" = lib.last (builtins.split ":" config.services.tor.torsocks.server);
          "network.connectivity-service.DNSv4.domain" = "127.0.0.1";
          "network.connectivity-service.DNSv6.domain" = "::1";
          "network.dns.localDomains" = "::1";
          "network.dns.forceResolve" = true;

          "extensions.formautofill.addresses.enabled" = false;
          "extensions.formautofill.creditCards.enabled" = false;

          "permissions.default.geo" = 2;
          "permissions.default.xr" = 2;
          "privacy.fingerprintingProtection" = true;
          "privacy.globalprivacycontrol.enabled" = true;
          "signon.firefoxRelay.feature" = "disabled";
          "browser.display.use_document_fonts" = 0;
          
          # "network.dns.DNS_HTTPS.domain" = "::1";
        } // optionalAttrs sway.enable { "browser.tabs.inTitlebar" = 0; };
      };
    };
  };

  options.grimmShared.firefox = with lib; {
    enable = mkEnableOption "grimm-firefox";

    plugins = mkOption {
      type = types.attrsOf types.str;
      default = { };
      description = "set of plugins to install. Format: guid = short-id";
    };

    disableUserPlugins = mkEnableOption "disables user controlled plugins";
  };
}