Blank Page on /u/login*

Knowledge Articles
1

Overview

This article explains how to resolve an issue causing a blank page on /u/login* when testing with a custom domain.

  • Network traffic on /u/login* shows the script or stylesheet calls returning 404s like this: https:///u/login/<URL_TO_YOUR_ASSET>

Applies To

  • New Universal Login with Custom Domain
  • Page Template
  • Advanced Customizations for Universal Login (ACUL) Advanced Rendering Mode

Cause

The ACUL advanced rendering mode feature was enabled following the steps listed in Enable ACUL advanced rendering mode without being fully configured.

Example configuration that causes this issue:

{

 "tenant": "<TENANT-NAME>",

 "prompt": "login-id",

 "screen": "login-id",

 "rendering_mode": "advanced",

 "context_configuration": [

  "screen.texts"

 ],

 "default_head_tags_disabled": false,

 "head_tags": [

  {

   "tag": "script",

   "attributes": {

    "src": "<URL_TO_YOUR_ASSET>",

    "async": true,

    "defer": true,

    "integrity": [

     "ASSET_SHA"

    ]

   }

  },

  {

   "tag": "link",

   "attributes": {

    "rel": "stylesheet",

    "href": "<URL_TO_YOUR_ASSET>"

   }

  }

 ]

}

Solution

Either disable the ACUL advanced rendering mode feature or replace the all caps placeholders (shown in the example above) with appropriate values.

Disable ACUL:

  1. via Management APIv2
PATCH to /api2/v2/prompts/{prompt}/screen/{screen}/rendering
{
  "rendering_mode": "standard"
}
  1. Via the Auth0 CLI:
    1. Open the Auth0 CLI
    2. Select Advanced
    3. Select the corresponding prompt and screen
    4. Set the rendering_mode to standard
    5. Deploy the changes

Related References