{
  config,
  inputs,
  lib,
  pkgs,
  ...
}:
with lib;
let
  cfg = config.nixfiles.modules.firefox;
in
{
  options.nixfiles.modules.firefox.enable = mkEnableOption "Firefox";

  config = mkIf cfg.enable {
    nixfiles.modules.common.xdg.defaultApplications.firefox = [
      "text/html"
      "x-scheme-handler/http"
      "x-scheme-handler/https"
    ];

    hm = {
      imports = [ inputs.arkenfox.hmModules.arkenfox ];

      home.packages = with pkgs; [ profile-cleaner ];

      stylix.targets.firefox = {
        enable = true;
        profileNames = [ "default" ];
      };

      programs.firefox = {
        enable = true;

        package = pkgs.firefox;

        arkenfox.enable = true;

        profiles.default =
          let
            mkCssWithRoot =
              css:
              mkMerge [
                # https://github.com/tinted-theming/base24/blob/master/styling.md
                (with config.colors.withHashtag; ''
                  :root {
                    --black: ${base01};
                    --red: ${base08};
                    --green: ${base0B};
                    --yellow: ${base09};
                    --blue: ${base0D};
                    --magenta: ${base0E};
                    --cyan: ${base0C};
                    --white: ${base06};
                    --bright-black: ${base02};
                    --bright-red: ${base12};
                    --bright-green: ${base14};
                    --bright-yellow: ${base13};
                    --bright-blue: ${base16};
                    --bright-magenta: ${base17};
                    --bright-cyan: ${base15};
                    --bright-white: ${base07};
                    --background: ${base00};
                    --foreground: ${base05};
                '')
                (
                  let
                    mapFonts = concatMapStringsSep ", " (font: ''"${font}"'');
                    size = toString config.stylix.fonts.sizes.applications;
                  in
                  with config.fonts.fontconfig.defaultFonts;
                  ''
                      --serif-font-family: ${mapFonts serif}, serif;
                      --serif-font-size: ${size};
                      --sans-serif-font-family: ${mapFonts sansSerif}, sans-serif;
                      --sans-serif-font-size: ${size};
                      --monospace-font-family: ${mapFonts monospace}, monospace;
                      --monospace-font-size: ${size};
                    }
                  ''
                )
                (builtins.readFile css)
              ];
          in
          {
            id = 0;

            isDefault = true;

            userChrome = mkCssWithRoot ./userChrome.css;

            userContent = mkCssWithRoot ./userContent.css;

            extensions =
              let
                # This was done using the incredible addon generator[1]. All credit
                # goes to Robert Helgesson.
                #
                # [1]: https://sr.ht/~rycee/mozilla-addons-to-nix/
                buildFirefoxXpiAddon = makeOverridable (
                  {
                    stdenv ? pkgs.stdenv,
                    fetchurl ? pkgs.fetchurl,
                    pname,
                    version,
                    addonId,
                    url,
                    sha256,
                    meta,
                    ...
                  }:
                  stdenv.mkDerivation {
                    name = "${pname}-${version}";
                    src = fetchurl { inherit url sha256; };
                    buildCommand = ''
                      install -Dm644 "$src" "$out/share/mozilla/extensions/{ec8030f7-c20a-464f-9b0e-13a3a9e97384}/${addonId}.xpi"
                    '';
                    inherit meta;
                  }
                );

                addons = import ./addons.nix { inherit buildFirefoxXpiAddon lib; };
              in
              with addons;
              [
                consent-o-matic
                darkreader
                furiganaize
                languagetool
                no-pdf-download
                redirector
                rikaichamp
                skip-redirect
                ublock-origin
                user-agent-switcher
                violentmonkey
              ]
              ++ optional config.nixfiles.modules.ipfs.enable ipfs-companion;

            search = {
              force = true;

              default = "DuckDuckGo";
              order = [ "DuckDuckGo" ];

              engines =
                let
                  getIcon = url: hash: pkgs.fetchurl { inherit url hash; };
                in
                {
                  "Amazon.com".metaData.hidden = true;
                  "Bing".metaData.hidden = true;
                  "Ebay".metaData.hidden = true;

                  "2GIS" = {
                    urls = [ { template = "https://2gis.ru/kazan/search/{searchTerms}"; } ];
                    icon = getIcon "https://d-assets.2gis.ru/favicon.png" "sha256-BlSaYRcUx9zhfJnVK5V7rsyft4qaueIEOONiCg+6aLE=";
                    definedAliases = [ "@2gis" ];
                  };

                  "AliExpress" = {
                    urls = [ { template = "https://aliexpress.ru/wholesale?SearchText={searchTerms}"; } ];
                    icon = getIcon "https://ae01.alicdn.com/images/eng/wholesale/icon/aliexpress.ico" "sha256-7xgem2pY2PNuv8as1YnS+U03GvDLLGjhcDLt69rtmaA=";
                    definedAliases = [
                      "@aliexpress"
                      "@ali"
                    ];
                  };

                  "Ansible Galaxy" = {
                    urls = [ { template = "https://galaxy.ansible.com/search?keywords={searchTerms}"; } ];
                    icon = getIcon "https://galaxy.ansible.com/assets/favicon.ico" "sha256-oAolpZhdKbVTraes6dDlafpvq/Vypu264vgKN4jzJk8=";
                    definedAliases = [
                      "@ansible"
                      "@galaxy"
                      "@ag"
                    ];
                  };

                  "Arch Wiki" = {
                    urls = [ { template = "https://wiki.archlinux.org/index.php?search={searchTerms}"; } ];
                    icon = getIcon "https://wiki.archlinux.org/favicon.ico" "sha256-0uxMtT8myzTT7p9k6v5UxsguPKu+vHPlglNTMbnN1T0=";
                    definedAliases = [
                      "@archwiki"
                      "@aw"
                    ];
                  };

                  "crates.io" = {
                    urls = [ { template = "https://crates.io/search?q={searchTerms}"; } ];
                    icon = getIcon "https://crates.io/favicon.ico" "sha256-upooA/+m5KMUD1t4WFY3EOmytdpUFgNqUj12Auta1mM=";
                    definedAliases = [ "@crates" ];
                  };

                  "Discogs" = {
                    urls = [ { template = "https://www.discogs.com/search?q={searchTerms}"; } ];
                    icon = getIcon "https://st.discogs.com/d56dcb7367720ea20f1b11a4385705517c7e7702/images/favicon.ico" "sha256-zEDrbmcUf8XHUyYzNc6JsWzBioX8sm8tjScGHim5VTk=";
                    definedAliases = [ "@discogs" ];
                  };

                  "Docker Hub" = {
                    urls = [ { template = "https://hub.docker.com/search?q={searchTerms}"; } ];
                    icon = getIcon "https://www.docker.com/wp-content/uploads/2023/04/cropped-Docker-favicon-32x32.png" "sha256-4NmHGMaq31qoIvdlmy7fI3qTbkcp1/tJhqQu/9Ci4/c=";
                    definedAliases = [
                      "@dockerhub"
                      "@docker"
                    ];
                  };

                  "Ecosia" = {
                    urls = [ { template = "https://www.ecosia.org/search?q={searchTerms}"; } ];
                    icon = getIcon "https://cdn-static.ecosia.org/static/icons/favicon.ico" "sha256-uvPShG1yVh4C4zaJmGuhhr96V/NredB1Wte9O3U6QxA=";
                    definedAliases = [ "@ecosia" ];
                  };

                  "Genius" = {
                    urls = [ { template = "https://genius.com/search?q={searchTerms}"; } ];
                    icon = getIcon "https://assets.genius.com/images/apple-touch-icon.png" "sha256-M9YQEVg3T7hMO/xPfihR1aXfG+/pNiVOBCOtzx3GrkE=";
                    definedAliases = [ "@genius" ];
                  };

                  "GitHub" = {
                    urls = [ { template = "https://github.com/search?q={searchTerms}"; } ];
                    icon = getIcon "https://github.githubassets.com/favicons/favicon-dark.svg" "sha256-qu/d9ftvsntplFuxw9RFL8BpI9b2g5b6xfeGw6Ekh6w=";
                    definedAliases = [
                      "@github"
                      "@gh"
                    ];
                  };

                  "godocs.io" = {
                    urls = [ { template = "https://godocs.io/?q={searchTerms}"; } ];
                    icon = getIcon "https://go.dev/images/favicon-gopher.svg" "sha256-OlKpUUeYF8TtMoX4e0ERK1ocIb53OJ8ZDxvwJaQVM/0=";
                    definedAliases = [ "@godocs" ];
                  };

                  "pkgs.go.dev" = {
                    urls = [ { template = "https://pkg.go.dev/search?q={searchTerms}"; } ];
                    icon = getIcon "https://go.dev/images/favicon-gopher.svg" "sha256-OlKpUUeYF8TtMoX4e0ERK1ocIb53OJ8ZDxvwJaQVM/0=";
                    definedAliases = [ "@gopkgs" ];
                  };

                  "Hackage" = {
                    urls = [ { template = "https://hackage.haskell.org/packages/search?terms={searchTerms}"; } ];
                    icon = getIcon "https://hackage.haskell.org/static/favicon.png" "sha256-+6WAv93yaA3L2eheGKxklY/uRAvbKD1q/WcmufmhKxY=";
                    definedAliases = [ "@hackage" ];
                  };

                  "Hoogle" = {
                    urls = [ { template = "https://hoogle.haskell.org/?hoogle={searchTerms}"; } ];
                    icon = getIcon "https://hoogle.haskell.org/favicon.png" "sha256-6qmjRYDDRUwm6EdLoZB6o9XtoujsfDEQJ9xOu3Knei8=";
                    definedAliases = [ "@hoogle" ];
                  };

                  "Jisho" = {
                    urls = [ { template = "https://jisho.org/search/{searchTerms}"; } ];
                    icon = getIcon "https://assets.jisho.org/assets/favicon-062c4a0240e1e6d72c38aa524742c2d558ee6234497d91dd6b75a182ea823d65.ico" "sha256-BixKAkDh5tcsOKpSR0LC1VjuYjRJfZHda3WhguqCPWU=";
                    definedAliases = [ "@jisho" ];
                  };

                  "コトバンク" = {
                    urls = [ { template = "https://kotobank.jp/gs/?q={searchTerms}"; } ];
                    icon = getIcon "https://kotobank.jp/favicon.ico" "sha256-t+EzqURlQwznuBqa0GcBbqumvZqtU7HrEAjGUlqp1tg=";
                    definedAliases = [ "@kotobank" ];
                  };

                  "Kubernetes" = {
                    urls = [ { template = "https://kubernetes.io/search/?q={searchTerms}"; } ];
                    icon = getIcon "https://kubernetes.io/images/kubernetes.png" "sha256-YI5QvGQXoaTG3uUGQ/R99Xl2r+VqBAA1qqthzPbf8nQ=";
                    definedAliases = [
                      "@kubernetes"
                      "@k8s"
                    ];
                  };

                  "Last.fm" = {
                    urls = [ { template = "https://www.last.fm/search?q={searchTerms}"; } ];
                    icon = getIcon "https://www.last.fm/static/images/favicon.702b239b6194.ico" "sha256-ID+DfF+dZ5CzKiBp/psQPRD6r/06PZ0rVYiELWUt5Mw=";
                    definedAliases = [ "@lastfm" ];
                  };

                  "MDN" = {
                    urls = [ { template = "https://developer.mozilla.org/en-US/search?q={searchTerms}"; } ];
                    icon = getIcon "https://developer.mozilla.org/favicon-48x48.cbbd161b.png" "sha256-Wnd0BqQIKgroGmV+R8vqV9uNBwDvcxBrQ8hXOLOFeKY=";
                    definedAliases = [ "@mdn" ];
                  };

                  "MELPA" = {
                    urls = [ { template = "https://melpa.org/#/?q={searchTerms}"; } ];
                    icon = getIcon "https://melpa.org/favicon.ico" "sha256-bmlydqXBM8MUMC6cOTGSHPx6zN8tZFqmQ+srbXkSCA4=";
                    definedAliases = [ "@melpa" ];
                  };

                  "MusicBrainz" = {
                    urls = [ { template = "https://musicbrainz.org/search?type=artist&query={searchTerms}"; } ];
                    icon = getIcon "https://musicbrainz.org/static/images/favicons/favicon-16x16.png" "sha256-M5mKQurmO9AP0gfC+5OLwi8k4XWQy759eQrrKAeytl0=";
                    definedAliases = [
                      "@musicbrainz"
                      "@mb"
                    ];
                  };

                  "NixOS Packages" = {
                    urls = [ { template = "https://search.nixos.org/packages?channel=unstable&query={searchTerms}"; } ];
                    icon = getIcon "https://nixos.org/favicon.png" "sha256-awcsDbbpRcDJnJpRavj/IcKMReEektRcqKbE35IJTKQ=";
                    definedAliases = [
                      "@nixpkgs"
                      "@np"
                    ];
                  };

                  "NixOS Options" = {
                    urls = [ { template = "https://search.nixos.org/options?channel=unstable&query={searchTerms}"; } ];
                    icon = getIcon "https://nixos.org/favicon.png" "sha256-awcsDbbpRcDJnJpRavj/IcKMReEektRcqKbE35IJTKQ=";
                    definedAliases = [
                      "@nixopts"
                      "@no"
                    ];
                  };

                  "NixOS Wiki" = {
                    urls = [ { template = "https://wiki.nixos.org/index.php?search={searchTerms}"; } ];
                    icon = getIcon "https://wiki.nixos.org/favicon.ico" "sha256-88EXiL5AoP56bgteo2YXI00iK9cmd7DVg+RMbFxy6+k=";
                    definedAliases = [
                      "@nixoswiki"
                      "@nw"
                    ];
                  };

                  "OpenStreetMap" = {
                    urls = [ { template = "https://www.openstreetmap.org/search?query={searchTerms}"; } ];
                    icon = getIcon "https://www.openstreetmap.org/assets/favicon-32x32-99b88fcadeef736889823c8a886b89d8cada9d4423a49a27de29bacc0a6bebd1.png" "sha256-dt4QVbQPdb4neS/fwH3yOWOSbEdkjMZtAYnIeCfr7qI=";
                    definedAliases = [
                      "@openstreetmap"
                      "@osm"
                      "@maps"
                    ];
                  };

                  "ProtonDB" = {
                    urls = [ { template = "https://www.protondb.com/search?q={searchTerms}"; } ];
                    icon = getIcon "https://www.protondb.com/sites/protondb/images/favicon.ico" "sha256-oauOp0EASNjMcThfzYJ2TfbaOYHBPL8LOp+9lmp4pmc=";
                    definedAliases = [ "@protondb" ];
                  };

                  "PyPI" = {
                    urls = [ { template = "https://pypi.org/search/?q={searchTerms}"; } ];
                    icon = getIcon "https://pypi.org/static/images/logo-small.2a411bc6.svg" "sha256-+fcSfcNxAMLIFkp+gh52c48lQORoyhcegUIFtuq/zYs=";
                    definedAliases = [ "@pypi" ];
                  };

                  "Python Docs" = {
                    urls = [ { template = "https://docs.python.org/3/search.html?q={searchTerms}"; } ];
                    icon = getIcon "https://docs.python.org/3/_static/py.svg" "sha256-WGW+i8wK+IhZSQPqARL2yNkjxXJsQIHoyFYRDMcznO8=";
                    definedAliases = [ "@pydocs" ];
                  };

                  "Rate Your Music" = {
                    urls = [ { template = "https://rateyourmusic.com/search?searchterm={searchTerms}"; } ];
                    icon = getIcon "https://e.snmc.io/3.0/img/logo/sonemic-32.png" "sha256-JpTt1tjBkUvDMTGrG7Hg2EiE8PR3RL7McodeZk1EpZA=";
                    definedAliases = [ "@rym" ];
                  };

                  "Rust Std" = {
                    urls = [ { template = "https://doc.rust-lang.org/std/?search={searchTerms}"; } ];
                    icon = getIcon "https://www.rust-lang.org/static/images/favicon-32x32.png" "sha256-l2y4jpnODbua4dyLvXTMBlHVkoDPM9y00l6L61so7eA=";
                    definedAliases = [
                      "@ruststd"
                      "@rust"
                    ];
                  };

                  "SourceHut" = {
                    urls = [ { template = "https://sr.ht/projects?search={searchTerms}"; } ];
                    icon = getIcon "https://sr.ht/static/logo.png" "sha256-NBzKZhqE9//zVJlOwYiwyW/jRFh8+nS2YvC3zMCQ1fU=";
                    definedAliases = [
                      "@sourcehut"
                      "@srht"
                    ];
                  };

                  "SteamDB" = {
                    urls = [ { template = "https://steamdb.info/search/?a=app&q={searchTerms}"; } ];
                    icon = getIcon "https://steamdb.info/static/logos/32px.png" "sha256-IUBiB5JUSvyDa+m/wecmHB8s3Wfu0JK98bJ+ZRZ5ybQ=";
                    definedAliases = [ "@steamdb" ];
                  };

                  "WolframAlpha" = {
                    urls = [ { template = "https://www.wolframalpha.com/input?i={searchTerms}"; } ];
                    icon = getIcon "https://www.wolframalpha.com/_next/static/images/favicon_1zbE9hjk.ico" "sha256-S9k7AlBQiDElBCGopJ8xfBD6dIhGU+EBh8t1QYbP2S4=";
                    definedAliases = [
                      "@wolframalpha"
                      "@wa"
                    ];
                  };

                  "Yandex" = {
                    urls = [ { template = "https://yandex.ru/search/?text={searchTerms}"; } ];
                    icon = getIcon "https://yastatic.net/s3/web4static/_/v2/oxjfXL1EO-B5Arm80ZrL00p0al4.png" "sha256-gvYh4oCZEO7BL2QZ6QvQFlmFiP2L4SLJrxAsKFcG6G4=";
                    definedAliases = [
                      "@yandex"
                      "@ya"
                    ];
                  };

                  "YouTube" = {
                    urls = [ { template = "https://yewtu.be/search?q={searchTerms}"; } ];
                    icon = getIcon "https://www.youtube.com/s/desktop/280a3f09/img/favicon.ico" "sha256-i7HQ+kOhdDbVndVG9vdMdtxEc13vdSLCLYAxFm24kR0=";
                    definedAliases = [
                      "@youtube"
                      "@yt"
                    ];
                  };
                };
            };

            # NOTE This silently overrides all other bookmarks.
            bookmarks = [
              {
                name = "Bookmarks Toolbar";
                toolbar = true;
                bookmarks = with config.nixfiles.modules; [
                  (mkIf syncthing.enable {
                    name = "Syncthing";
                    url = "http://${config.services.syncthing.guiAddress}";
                  })
                  (mkIf ipfs.enable {
                    name = "IPFS";
                    url = "http://127.0.0.1:${toString ipfs.apiPort}/webui";
                  })
                ];
              }
            ];

            # https://github.com/arkenfox/user.js/blob/master/user.js
            arkenfox = {
              enable = true;
              "0000".enable = true;
              "0100" = {
                enable = true;
                "0103"."browser.startup.homepage".value = "about:blank";
              };
              "0200".enable = true;
              "0300".enable = true;
              "0400".enable = true;
              "0600".enable = true;
              "0700" = {
                enable = true;
                "0710"."network.trr.mode" = {
                  enable = true;
                  value = 5;
                };
              };
              "0800".enable = true;
              "0900".enable = true;
              "1000" = {
                enable = true;
                "1001".enable = false;
              };
              "1200".enable = true;
              "1600".enable = true;
              "1700".enable = true;
              "2000".enable = true;
              "2400".enable = true;
              "2600" = {
                enable = true;
                "2615"."permissions.default.shortcuts".enable = true;
              };
              "2700".enable = true;
              "2800" = {
                enable = true;
                "2811" = {
                  "privacy.clearOnShutdown.history".value = false;
                  "privacy.clearOnShutdown_v2.historyFormDataAndDownloads".value = false;
                };
                "2820"."privacy.clearSiteData.historyFormDataAndDownloads".value = false;
                "2830"."privacy.clearHistory.historyFormDataAndDownloads".value = false;
              };
              "4500" = {
                enable = true;
                "4502".enable = false;
                "4504".enable = false;
              };
              "5000" = {
                enable = true;
                "5003"."signon.rememberSignons".enable = true;
                "5010"."browser.urlbar.suggest.topsites".enable = true;
                "5017" = {
                  "extensions.formautofill.addresses.enabled".enable = true;
                  "extensions.formautofill.creditCards.enabled".enable = true;
                };
                "5019"."browser.pagethumbnails.capturing_disabled".enable = true;
              };
              "5500" = {
                enable = true;
                "5508" = {
                  "media.eme.enabled".enable = true;
                  "browser.eme.ui.enabled".enable = true;
                };
              };
              "6000".enable = true;
              "7000".enable = true;
              "8000".enable = true;
              "9000".enable = true;
            };

            settings = {
              "app.update.auto" = false;
              "browser.backspace_action" = 0;
              "browser.disableResetPrompt" = true;
              "browser.download.autohideButton" = false;
              "browser.newtabpage.introShown" = true;
              "browser.newtabpage.pinned" = "";
              "browser.onboarding.enabled" = false;
              "browser.open.lastDir" = config.my.home;
              "browser.protections_panel.infoMessage.seen" = true;
              "browser.region.update.region" = "US";
              "browser.search.region" = "US";
              "browser.search.separatePrivateDefault" = mkForce false;
              "browser.search.separatePrivateDefault.ui.enabled" = mkForce false;
              "browser.search.update" = false;
              "browser.shell.checkDefaultBrowser" = false;
              "browser.tabs.closeWindowWithLastTab" = true;
              "browser.tabs.firefox-view" = false;
              "browser.tabs.firefox-view-next" = false;
              "browser.tabs.inTitlebar" = 0;
              "browser.tabs.tabmanager.enabled" = false;
              "browser.tabs.warnOnClose" = false;
              "browser.tabs.warnOnCloseOtherTabs" = false;
              "browser.tabs.warnOnOpen" = false;
              "browser.toolbars.bookmarks.visibility" = "newtab";
              "browser.translations.enable" = false;
              "browser.urlbar.decodeURLsOnCopy" = true;
              "browser.urlbar.suggest.addons" = false;
              "browser.urlbar.suggest.bookmark" = true;
              "browser.urlbar.suggest.engines" = true;
              "browser.urlbar.suggest.history" = true;
              "browser.urlbar.suggest.openpage" = true;
              "browser.warnOnQuitShortcut" = false;
              "devtools.everOpened" = true;
              "doh-rollout.home-region" = "US";
              "extensions.pocket.enabled" = false;
              "extensions.update.autoUpdateDefault" = false;
              "extensions.update.enabled" = false;
              "full-screen-api.warning.delay" = 0;
              "full-screen-api.warning.timeout" = 0;
              "general.autoScroll" = true;
              "general.smoothScroll" = true;
              "identity.fxaccounts.enabled" = false;
              "media.autoplay.blocking_policy" = 2;
              "media.autoplay.default" = 5;
              "media.hardwaremediakeys.enabled" = false;
              "reader.parse-on-load.enabled" = false;
              "toolkit.legacyUserProfileCustomizations.stylesheets" = true;
            };
          };
      };
    };
  };
}