diff --git a/app.py b/app.py
index bad01e6..d0e04a9 100644
--- a/app.py
+++ b/app.py
@@ -89,6 +89,7 @@ talisman = Talisman(
     frame_options="DENY" if app.config.get("ENABLE_XFO", True) else None,
     content_security_policy=csp_policy,
     x_content_type_options=app.config.get("ENABLE_XCTO", True),
+    strict_transport_security_include_subdomains=False
 )
 
 register_heif_opener()  # pillow_heif dla HEIC