Form redirection to form-waiting is not occurring if there is a lambda

Bug Description

If a lambda node will be before the first Next Page form node then the form will be freezed until an ABL/proxy kills the session (in our case it's 60 seconds) after which the URL redirection from /form/ or /form-test/ to /form-waiting/ may or may not occur. If there is no ALB/proxy in front of n8n, then the execution will be completely hanged

with ALB and timeout setting of 60 secs

No ALB and the execution hanged.

Which may work if I resend the form request

To Reproduce

the workflow

{
  "meta": {
    "instanceId": "e56b502a7237cfd497427bf449a6e848ce88d35e16388a590c008c1c9e963d05"
  },
  "nodes": [
    {
      "parameters": {
        "function": "arn:aws:lambda:us-west-2:114025810846accountId:function:functionName",
        "qualifier": "stable",
        "payload": "{\"action\":\"help\"}"
      },
      "id": "e44ba5a3-5d9e-4b8b-a547-8c15354d166c",
      "name": "get graph endpoints",
      "type": "n8n-nodes-base.awsLambda",
      "typeVersion": 1,
      "position": [
        860,
        320
      ],
      "credentials": {
        "aws": {
          "id": "39dpCmpkOxSsq2il",
          "name": "AWS account"
        }
      }
    },
    {
      "parameters": {
        "formFields": {
          "values": [
            {
              "fieldLabel": "test",
              "placeholder": "test"
            }
          ]
        },
        "options": {
          "formDescription": "Choose Endpoint",
          "buttonLabel": "Next"
        }
      },
      "id": "d7cf01cf-a945-4dfe-8a15-04a424b1a6c2",
      "name": "Form graph endpoint",
      "type": "n8n-nodes-base.form",
      "typeVersion": 1,
      "position": [
        1120,
        320
      ],
      "webhookId": "a49c2294-8df9-4de7-9c91-e6252bdbffc9"
    },
    {
      "parameters": {
        "formTitle": "Lambda payload generator",
        "formDescription": "That form will return a payload for Code node or the ready-to-use node content",
        "formFields": {
          "values": [
            {
              "fieldLabel": "Press the Next button"
            }
          ]
        },
        "options": {
          "buttonLabel": "Next"
        }
      },
      "id": "414a171a-39f7-42de-82d8-aa5ece842185",
      "name": "On form submission",
      "type": "n8n-nodes-base.formTrigger",
      "typeVersion": 2.2,
      "position": [
        560,
        320
      ],
      "webhookId": "411cbebe-fa97-434b-a096-894992c9974d"
    }
  ],
  "connections": {
    "get graph endpoints": {
      "main": [
        [
          {
            "node": "Form graph endpoint",
            "type": "main",
            "index": 0
          }
        ]
      ]
    },
    "On form submission": {
      "main": [
        [
          {
            "node": "get graph endpoints",
            "type": "main",
            "index": 0
          }
        ]
      ]
    }
  },
  "pinData": {}
}

Expected behavior

a redirection to form-waiting will occur normally

Operating System

cloud, docker

n8n Version

1.66.0, 1.68.0

Node.js Version

cloud, docker

Database

SQLite (default)

Execution mode

main (default)

n8n-io / n8n