helm/modules/desktop/browsers/firefox.nix

# modules/browser/firefox.nix --- https://www.mozilla.org/en-US/firefox
#
# Oh firefox, gateway to the interwebs, devourer of ram. Give onto me your
# infinite knowledge and shelter me from ads.

{ options, config, lib, pkgs, ... }:

with lib;
with lib.my;
let cfg = config.modules.desktop.browsers.firefox;
in {
  options.modules.desktop.browsers.firefox = with types; {
    enable = mkBoolOpt false;
    profileName = mkOpt types.str config.user.name;

    settings = mkOpt' (attrsOf (oneOf [ bool int str ])) {} ''
      Firefox preferences to set in <filename>user.js</filename>
    '';
    extraConfig = mkOpt' lines "" ''
      Extra lines to add to <filename>user.js</filename>
    '';

    userChrome  = mkOpt' lines "" "CSS Styles for Firefox's interface";
    userContent = mkOpt' lines "" "Global CSS Styles for websites";
  };

  config = mkIf cfg.enable (mkMerge [
    {
      user.packages = with pkgs; [
        firefox-bin
        (makeDesktopItem {
          name = "firefox-private";
          desktopName = "Firefox (Private)";
          genericName = "Open a private Firefox window";
          icon = "firefox";
          exec = "${firefox-bin}/bin/firefox --private-window";
          categories = "Network";
        })
      ];

      # Prevent auto-creation of ~/Desktop. The trailing slash is necessary; see
      # https://bugzilla.mozilla.org/show_bug.cgi?id=1082717
      env.XDG_DESKTOP_DIR = "$HOME/";

      modules.desktop.browsers.firefox.settings = {
        "devtools.theme" = "dark";
        # Enable userContent.css and userChrome.css for our theme modules
        "toolkit.legacyUserProfileCustomizations.stylesheets" = true;
        # Stop creating ~/Downloads!
        "browser.download.dir" = "${config.user.home}/downloads";
        # Don't use the built-in password manager; a nixos user is more likely
        # using an external one (you are using one, right?).
        "signon.rememberSignons" = false;
        # Do not check if Firefox is the default browser
        "browser.shell.checkDefaultBrowser" = false;
        # Disable the "new tab page" feature and show a blank tab instead
        # https://wiki.mozilla.org/Privacy/Reviews/New_Tab
        # https://support.mozilla.org/en-US/kb/new-tab-page-show-hide-and-customize-top-sites#w_how-do-i-turn-the-new-tab-page-off
        "browser.newtabpage.enabled" = false;
        "browser.newtab.url" = "about:blank";
        # Disable Activity Stream
        # https://wiki.mozilla.org/Firefox/Activity_Stream
        "browser.newtabpage.activity-stream.enabled" = false;
        # Disable new tab tile ads & preload
        # http://www.thewindowsclub.com/disable-remove-ad-tiles-from-firefox
        # http://forums.mozillazine.org/viewtopic.php?p=13876331#p13876331
        # https://wiki.mozilla.org/Tiles/Technical_Documentation#Ping
        # https://gecko.readthedocs.org/en/latest/browser/browser/DirectoryLinksProvider.html#browser-newtabpage-directory-source
        # https://gecko.readthedocs.org/en/latest/browser/browser/DirectoryLinksProvider.html#browser-newtabpage-directory-ping
        "browser.newtabpage.enhanced" = false;
        "browser.newtab.preload" = false;
        "browser.newtabpage.directory.ping" = "";
        "browser.newtabpage.directory.source" = "data:text/plain,{}";
        # Disable some not so useful functionality.
        "media.videocontrols.picture-in-picture.video-toggle.enabled" = false;
        "extensions.htmlaboutaddons.recommendations.enabled" = false;
        "extensions.htmlaboutaddons.discover.enabled" = false;
        "extensions.pocket.enabled" = false;
        "app.normandy.enabled" = false;
        "app.normandy.api_url" = "";
        "extensions.shield-recipe-client.enabled" = false;
        "app.shield.optoutstudies.enabled" = false;
        # Disable battery API
        # https://developer.mozilla.org/en-US/docs/Web/API/BatteryManager
        # https://bugzilla.mozilla.org/show_bug.cgi?id=1313580
        "dom.battery.enabled" = false;
        # Disable "beacon" asynchronous HTTP transfers (used for analytics)
        # https://developer.mozilla.org/en-US/docs/Web/API/navigator.sendBeacon
        "beacon.enabled" = false;
        # Disable pinging URIs specified in HTML <a> ping= attributes
        # http://kb.mozillazine.org/Browser.send_pings
        "browser.send_pings" = false;
        # Disable gamepad API to prevent USB device enumeration
        # https://www.w3.org/TR/gamepad/
        # https://trac.torproject.org/projects/tor/ticket/13023
        "dom.gamepad.enabled" = false;
        # Don't try to guess domain names when entering an invalid domain name in URL bar
        # http://www-archive.mozilla.org/docs/end-user/domain-guessing.html
        "browser.fixup.alternate.enabled" = false;
        # Disable telemetry
        # https://wiki.mozilla.org/Platform/Features/Telemetry
        # https://wiki.mozilla.org/Privacy/Reviews/Telemetry
        # https://wiki.mozilla.org/Telemetry
        # https://www.mozilla.org/en-US/legal/privacy/firefox.html#telemetry
        # https://support.mozilla.org/t5/Firefox-crashes/Mozilla-Crash-Reporter/ta-p/1715
        # https://wiki.mozilla.org/Security/Reviews/Firefox6/ReviewNotes/telemetry
        # https://gecko.readthedocs.io/en/latest/browser/experiments/experiments/manifest.html
        # https://wiki.mozilla.org/Telemetry/Experiments
        # https://support.mozilla.org/en-US/questions/1197144
        # https://firefox-source-docs.mozilla.org/toolkit/components/telemetry/telemetry/internals/preferences.html#id1
        "toolkit.telemetry.enabled" = false;
        "toolkit.telemetry.unified" = false;
        "toolkit.telemetry.archive.enabled" = false;
        "experiments.supported" = false;
        "experiments.enabled" = false;
        "experiments.manifest.uri" = "";
        # Disable health reports (basically more telemetry)
        # https://support.mozilla.org/en-US/kb/firefox-health-report-understand-your-browser-perf
        # https://gecko.readthedocs.org/en/latest/toolkit/components/telemetry/telemetry/preferences.html
        "datareporting.healthreport.uploadEnabled" = false;
        "datareporting.healthreport.service.enabled" = false;
        "datareporting.policy.dataSubmissionEnabled" = false;
      };

      # Use a stable profile name so we can target it in themes
      home.file = let cfgPath = ".mozilla/firefox"; in {
        "${cfgPath}/profiles.ini".text = ''
          [Profile0]
          Name=default
          IsRelative=1
          Path=${cfg.profileName}.default
          Default=1

          [General]
          StartWithLastProfile=1
          Version=2
        '';

        "${cfgPath}/${cfg.profileName}.default/user.js" =
          mkIf (cfg.settings != {} || cfg.extraConfig != "") {
            text = ''
              ${concatStrings (mapAttrsToList (name: value: ''
                user_pref("${name}", ${builtins.toJSON value});
              '') cfg.settings)}
              ${cfg.extraConfig}
            '';
          };

        "${cfgPath}/${cfg.profileName}.default/chrome/userChrome.css" =
          mkIf (cfg.userChrome != "") {
            text = cfg.userChrome;
          };

        "${cfgPath}/${cfg.profileName}.default/chrome/userContent.css" =
          mkIf (cfg.userContent != "") {
            text = cfg.userContent;
          };
      };
    }
  ]);
}