diff --git a/modules/home-manager/all-modules.nix b/modules/home-manager/all-modules.nix
index 81c0450f..f9470910 100644
--- a/modules/home-manager/all-modules.nix
+++ b/modules/home-manager/all-modules.nix
@@ -10,6 +10,7 @@
   ./delta.nix
   ./dunst.nix
   ./fcitx5.nix
+  ./firefox.nix
   ./fish.nix
   ./foot.nix
   ./freetube.nix
diff --git a/modules/home-manager/firefox.nix b/modules/home-manager/firefox.nix
new file mode 100644
index 00000000..33c43b47
--- /dev/null
+++ b/modules/home-manager/firefox.nix
@@ -0,0 +1,65 @@
+{ catppuccinLib }:
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+
+let
+  inherit (config.catppuccin) sources;
+
+  mkFirefoxModule =
+    name:
+    let
+      cfg = config.catppuccin.${name};
+
+      # ID for the chosed theme's addon
+      addonId = sources.firefox.addonIds.${cfg.flavor}.${cfg.accent};
+      upperName = catppuccinLib.mkUpper name;
+    in
+    {
+      options.catppuccin.${name} =
+        catppuccinLib.mkCatppuccinOption {
+          inherit name;
+          accentSupport = true;
+        }
+        // {
+          finalPackage = lib.mkOption {
+            type = lib.types.package;
+            readOnly = true;
+            description = "Resulting ${upperName} package";
+          };
+          profiles = lib.mkOption {
+            type = with lib.types; listOf str;
+            description = "${upperName} profiles to install the Catppuccin theme addon on";
+            default = [ "default" ];
+            example = lib.literalExpression ''[ "default" "default-release" "work" ]'';
+          };
+        };
+      config = lib.mkIf cfg.enable {
+        catppuccin.${name}.finalPackage = pkgs.${name}.override (previous: {
+          extraPrefsFiles = (previous.extraPrefsFiles or [ ]) ++ [
+            (pkgs.writeTextFile {
+              name = "catppuccin.cfg";
+              text = ''
+                // Immutably set theme
+                lockPref("extensions.activeThemeID", "${addonId}");
+                // Immutably disable syncing the active theme to avoid issues just in case
+                lockPref("services.sync.prefs.sync.extensions.activeThemeID", false);
+              '';
+            })
+          ];
+        });
+        programs.${name} = {
+          profiles = lib.genAttrs cfg.profiles (_: { extensions = [ sources.firefox."${cfg.flavor}_${cfg.accent}" ]; })
+          package = cfg.finalPackage;
+        };
+      };
+    };
+in
+lib.foldl (acc: name: lib.recursiveUpdate acc (mkFirefoxModule name)) { } [
+  "firefox"
+  "floorp"
+  "librewolf"
+]
diff --git a/modules/tests/darwin.nix b/modules/tests/darwin.nix
index a3ab0bd4..5010f7e1 100644
--- a/modules/tests/darwin.nix
+++ b/modules/tests/darwin.nix
@@ -23,10 +23,13 @@
         programs = {
           cava.enable = lib.mkVMOverride false; # NOTE: this may actually work on darwin, but the package is currently not supported
           chromium.enable = lib.mkVMOverride false;
+          firefox.enable = lib.mkVMOverride false; # NOTE: Not available on darwin
+          floorp.enable = lib.mkVMOverride false; # NOTE: same as firefox
           foot.enable = lib.mkVMOverride false;
           fuzzel.enable = lib.mkVMOverride false;
           hyprlock.enable = lib.mkVMOverride false;
           imv.enable = lib.mkVMOverride false;
+          librewolf.enable = lib.mkVMOverride false; # NOTE: same as firefox
           mpv.enable = lib.mkVMOverride false; # NOTE: same as cava, but `mpv` fails to build currently
           obs-studio.enable = lib.mkVMOverride false;
           rio.enable = lib.mkVMOverride false; # marked as broken
diff --git a/modules/tests/home.nix b/modules/tests/home.nix
index 99374e93..9acaecfb 100644
--- a/modules/tests/home.nix
+++ b/modules/tests/home.nix
@@ -26,7 +26,9 @@
     btop.enable = true;
     cava.enable = true;
     chromium.enable = true;
+    firefox.enable = true;
     fish.enable = true;
+    floorp.enable = true;
     foot.enable = true;
     freetube.enable = true;
     fuzzel.enable = true;
@@ -46,6 +48,7 @@
     k9s.enable = true;
     kitty.enable = true;
     lazygit.enable = true;
+    librewolf.enable = true;
     micro.enable = true;
     mpv.enable = true;
     neovim.enable = true;
diff --git a/pkgs/firefox/package.nix b/pkgs/firefox/package.nix
new file mode 100644
index 00000000..dd853081
--- /dev/null
+++ b/pkgs/firefox/package.nix
@@ -0,0 +1,129 @@
+{
+  buildCatppuccinPort,
+  fetchFromGitHub,
+  lib,
+}:
+buildCatppuccinPort (finalAttrs: rec {
+  pname = "firefox";
+
+  src = fetchFromGitHub {
+    owner = "catppuccin";
+    repo = "firefox";
+    rev = "refs/tags/old";
+    hash = "sha256-ZIK0LX8OJOBr20diRDQRrNc1X+q3DtHNcc/dRZU2QfM=";
+  };
+
+  # installTargets = [ "releases/old" ];
+
+  # Split package into outputs of each flavor/accent combination
+  # in order to avoid polluting the user's extensions and flooding them with extension installed notifications
+  # "out" is just there to avoid a build error
+  outputs =
+    [
+      "out"
+    ]
+    ++ (lib.flatten (
+      lib.mapAttrsToList (
+        flavor: accents: (lib.mapAttrsToList (accent: _: "${flavor}_${accent}") accents)
+      ) passthru.addonIds
+    ));
+
+  # There is a build script in $src that we do not want to run
+  dontBuild = true;
+  dontCatppuccinInstall = true;
+
+  installPhase = ''
+    runHook preInstallHook
+
+    # Create $out just to avoid a build error
+    mkdir $out
+
+    ${lib.concatStrings (
+      lib.flatten (
+        lib.mapAttrsToList (
+          flavor: accents:
+          (lib.mapAttrsToList (
+            accent: id:
+            # Code adapted from `buildFirefoxXpiAddon` from
+            # https://github.com/nix-community/nur-combined/blob/master/repos/rycee/pkgs/firefox-addons/default.nix
+            ''
+              dst="''$${flavor}_${accent}/share/mozilla/extensions/{ec8030f7-c20a-464f-9b0e-13a3a9e97384}"
+              mkdir -p "$dst"
+              install -v -m644 "$src/releases/old/catppuccin_${flavor}_${accent}.xpi" "$dst/${id}.xpi"
+            '') accents)
+        ) finalAttrs.finalPackage.addonIds
+      )
+    )}
+
+    runHook postInstallHook
+  '';
+
+  # Each Firefox addon has an ID used to refer to it in the config
+  # Unfortunately, the Catppuccin addons just use randomly generated ones
+  passthru.addonIds = {
+    latte = {
+      rosewater = "{42698af3-f4a0-4864-8a72-236e99d30345}";
+      flamingo = "{80a64fa5-f058-482c-a2fc-ec0c329a5910}";
+      pink = "{7f327fa3-57ad-4f5a-a638-0c8620df3cad}";
+      mauve = "{c827c446-3d00-4160-a992-3ebcbe6d81a6}";
+      red = "{7d4f99bc-5b1c-4e97-b1c1-cae24282eb71}";
+      maroon = "{1f6e25ab-cdbe-4a7a-90fb-911ced38df69}";
+      peach = "{6ea607a1-ee07-4f56-8349-5a257725b6c9}";
+      yellow = "{fbf67366-a9d5-40fb-aa10-5e2eb7d74d08}";
+      green = "{98439b1c-46b2-4e72-8b58-7b996112f199}";
+      teal = "{556ffa71-63b9-4ab8-822d-feb18097f961}";
+      sky = "{0711a452-8a57-4697-9ee2-5161fc77fe89}";
+      sapphire = "{fe7fd83c-01c2-4de1-b055-fdcc122e94fb}";
+      blue = "{68f3538d-3881-45f4-aa73-288b010b39a1}";
+      lavender = "{bc6fdbef-4c18-4967-9899-7803fdcaf3b4}";
+    };
+    frappe = {
+      rosewater = "{d39d5a2f-2f99-4744-b904-793881cbc306}";
+      flamingo = "{cb69ead4-b74b-4efa-a49b-8d921eca8947}";
+      pink = "{b6129aa9-e45d-4280-aac8-3654e9d89d21}";
+      mauve = "{5630de1f-49cb-41ef-934d-2343026b25a5}";
+      red = "{32577cb5-8803-4b2b-8d9c-f962ef0ce277}";
+      maroon = "{d2b153b6-07ae-46ea-8f79-cae317fd8be0}";
+      peach = "{89d0f64f-9088-4b50-861e-35c50c0ef909}";
+      yellow = "{0146c14f-d2b3-4b1e-8e93-7cb301c231fc}";
+      green = "{106ca6d4-1fbf-4665-b968-88a3ff31de3a}";
+      teal = "{615b2812-7ab8-4ea5-bb8a-c62bf4b1a4b1}";
+      sky = "{c7cf6786-24b7-4bd2-ae71-b985fcc98f20}";
+      sapphire = "{c52d6318-7734-4ac5-a909-2f12b0f0f3b1}";
+      blue = "{0f28d17a-46f0-4fe1-8696-1676de0a87f2}";
+      lavender = "{5ee380f7-abda-467c-ae9a-d30bf8f0d1d6}";
+    };
+    macchiato = {
+      rosewater = "{a5726845-3a00-4076-8601-b9b943dfcddc}";
+      flamingo = "{03f8dbf5-5054-44b3-9443-4bb24d981e90}";
+      pink = "{e554e180-24a4-40a2-911d-bf48d5b1629c}";
+      mauve = "{998d0435-a079-4dcc-ad24-7333b3463bca}";
+      red = "{a5c9c2ff-855c-4c6e-a0f0-52e7c1b48a01}";
+      maroon = "{4c302124-e622-4a6a-9a9e-55ffde4e80a9}";
+      peach = "{4dfd877b-8072-4d5b-b271-768bbdc78e53}";
+      yellow = "{b7582732-61a1-4708-b726-73691837fedd}";
+      green = "{5dff4698-8117-41cd-8377-de57f671d736}";
+      teal = "{658bd4ed-c245-454a-8fd6-fd9de5e1b046}";
+      sky = "{5d96985c-7004-413b-bd17-3a0e334d898b}";
+      sapphire = "{32ff0ff3-110d-4c2e-9134-005bba3f1b64}";
+      blue = "{d49033ac-8969-488c-afb0-5cdb73957f41}";
+      lavender = "{15cb5e64-94bd-41aa-91cf-751bb1a84972}";
+    };
+    mocha = {
+      rosewater = "{5b78178f-135d-4df2-821f-1f289be7f348}";
+      flamingo = "{49783482-0579-4c89-9b46-674b2c8d3c53}";
+      pink = "{0a2d1098-69a9-4e98-a62c-a861766ac24d}";
+      mauve = "{76aabc99-c1a8-4c1e-832b-d4f2941d5a7a}";
+      red = "{6f70b243-f2a4-4e65-ab41-4e75a6efb65a}";
+      maroon = "{48a265ac-f603-4262-b0e7-2a55c159aaef}";
+      peach = "{3a271e29-2654-4dcc-9186-745deca0b17f}";
+      yellow = "{b99d94a7-f494-49b1-8dc1-face82d0a941}";
+      green = "{f4363cd3-9ba9-453d-b2b2-66e6e1bafe73}";
+      teal = "{409be3b6-54bf-47c8-83d2-9bd43e0730e3}";
+      sky = "{1ac25999-353e-49bf-a064-1d0690bb3ec9}";
+      sapphire = "{b2e54022-c8a0-444f-8d7c-bc7282cadbd2}";
+      blue = "{2adf0361-e6d8-4b74-b3bc-3f450e8ebb69}";
+      lavender = "{8446b178-c865-4f5c-8ccc-1d7887811ae3}";
+    };
+  };
+})