diff --git a/build.py b/build.py
new file mode 100644
index 0000000..c0a0013
--- /dev/null
+++ b/build.py
@@ -0,0 +1,101 @@
+import os
+import re
+import shutil
+import tempfile
+import zipfile
+
+SCRIPT_NAME = os.path.basename(__file__)
+TARGET_FILE = "manifest.json"
+
+
+def zip_folder(output_name, folder, exclude_files, exclude_dirs):
+    with zipfile.ZipFile(output_name, "w", zipfile.ZIP_DEFLATED) as zipf:
+        for root, dirs, files in os.walk(folder):
+            # Exclude specified directories
+            dirs[:] = [
+                d
+                for d in dirs
+                if os.path.join(root, d).replace(folder + os.sep, "")
+                not in exclude_dirs
+            ]
+
+            for file in files:
+                rel_path = os.path.relpath(os.path.join(root, file), folder)
+                if (
+                    file in exclude_files
+                    or rel_path in exclude_files
+                    or any(rel_path.startswith(ed + os.sep) for ed in exclude_dirs)
+                ):
+                    continue
+                zipf.write(os.path.join(root, file), arcname=rel_path)
+
+
+def update_version_line(file_path, new_base_version):
+    with open(file_path, "r", encoding="utf-8") as f:
+        lines = f.readlines()
+
+    new_version = f"{new_base_version}.0"
+    updated = False
+
+    for i, line in enumerate(lines):
+        match = re.match(r'\s*"version":\s*"([^"]+)"', line)
+        if match:
+            old_version = match.group(1)
+            lines[i] = re.sub(
+                r'"version":\s*".+?"', f'"version": "{new_version}"', line
+            )
+            updated = True
+            print(f"🛠️ Changed version from {old_version} ➜ {new_version}")
+            break
+
+    if updated:
+        with open(file_path, "w", encoding="utf-8") as f:
+            f.writelines(lines)
+    else:
+        print("⚠️ No version line found to update.")
+
+
+def main():
+    base_version = input("Enter the new base version (e.g., 1.2.2): ").strip()
+    if not base_version:
+        print("❌ No version entered. Exiting.")
+        return
+
+    current_dir = os.getcwd()
+    exclude_files = [SCRIPT_NAME] + [
+        f for f in os.listdir(current_dir) if f.endswith(".xpi")
+    ]
+    exclude_dirs = [".git"]
+
+    # 1. Create videospeed-github.xpi
+    zip_folder("videospeed-github.xpi", current_dir, exclude_files, exclude_dirs)
+    print("✅ Created videospeed-github.xpi")
+
+    # 2. Prepare temporary folder
+    with tempfile.TemporaryDirectory() as temp_dir:
+        for item in os.listdir(current_dir):
+            if item in exclude_files or item in exclude_dirs:
+                continue
+            s = os.path.join(current_dir, item)
+            d = os.path.join(temp_dir, item)
+            if os.path.isdir(s):
+                shutil.copytree(s, d)
+            else:
+                shutil.copy2(s, d)
+
+        # 3. Modify manifest.json version
+        manifest_path = os.path.join(temp_dir, TARGET_FILE)
+        if os.path.exists(manifest_path):
+            update_version_line(manifest_path, base_version)
+        else:
+            print(f"⚠️ {TARGET_FILE} not found in copied files.")
+
+        # 4. Zip modified files
+        zip_folder(
+            "videospeed-firefox.xpi", temp_dir, exclude_files=[], exclude_dirs=[]
+        )
+        print("✅ Created videospeed-firefox.xpi")
+
+
+if __name__ == "__main__":
+    main()
diff --git a/manifest.json b/manifest.json
index ad173c3..4a260d8 100644
--- a/manifest.json
+++ b/manifest.json
@@ -1,7 +1,7 @@
 {
   "name": "Video Speed Controller",
   "short_name": "videospeed",
-  "version": "1.2.1.0",
+  "version": "1.2.2",
   "manifest_version": 2,
   "description": "Speed up, slow down, advance and rewind HTML5 audio/video with shortcuts",
   "homepage_url": "https://github.com/SoPat712/videospeed",