diff --git a/package_build/i18n.py b/package_build/i18n.py
index ea3d8f2..5bdf778 100644
--- a/package_build/i18n.py
+++ b/package_build/i18n.py
@@ -6,8 +6,9 @@
 
 
 def get_preferred_languages() -> list[str]:
-    headers = _get_websocket_headers()
-    return re.findall(r"([a-zA-Z-]{2,})", headers["Accept-Language"]) or []
+    headers = _get_websocket_headers() or {}
+    accept_language = headers.get("Accept-Language") or ""
+    return re.findall(r"([a-zA-Z-]{2,})", accept_language) or []
 
 
 locale_dir = Path(__file__).parent / "locale"