Good evening!
I have a flow in n8n that consists of: webhook (GET) → JavaScript with HTML → respond to webhook.
The page is a login page, and when it tries to set a cookie on the page, I get the following error:
“Failed to set the ‘cookie’ property on ‘Document’: The document is sandboxed and lacks the ‘allow-same-origin’ flag.”
After some research, I found out that this happens because of a change in n8n, where now every HTML page is loaded inside an iframe/sandbox.
I saw that it’s possible to disable this using an environment variable:
N8N_INSECURE_DISABLE_WEBHOOK_IFRAME_SANDBOX, which, when set to true, disables it.
However, even after disabling it, it still doesn’t work. I’m testing this locally using Docker Desktop, and it’s not working. Even after disabling it, I still get the same error shown above.
I’m using a basic n8n installation setup as shown in the official documentation, the only difference is the last environment variable I added to disable this feature.
The workflow in question is one I found in a video, and the creator made it available. The workflow is in the link below.