I Receive an Error When Opening TidyUp

Instructors receive a fatal error when launching TidyUp in Canvas due to blocked third-party cookies. Allowing cookies in the browser resolves the OIDC authentication failure.

Quick Links: | Environment | Solution | Root Cause |

When attempting to open the TidyUp tool in Canvas, users receive a fatal error message that includes "OIDC flow failed" and a reference to missing information in OidcClient.php. As a result, the tool fails to load and cannot be used. This issue prevents instructors from cleaning up unused files in their Canvas course.

Environment

This article is relevant to you if:

• You are using the TidyUp tool within a Canvas course

• You see an error message that includes OIDC flow failed or Missing information. Example:

  Fatal error: Uncaught Exception: Missing information. OIDC flow failed. in /var/www/html/lib/lti13/OidcClient.php:28 Stack trace: #0 /var/www/html/public/lti13resp.php(6): OidcClient->__construct() #1 {main} thrown in /var/www/html/lib/lti13/OidcClient.php on line 28 
  

• You are using a browser that may have strict privacy settings or blocked third-party cookies

TidyUp is a third-party LTI (Learning Tools Interoperability) integration that launches using the LTI 1.3 protocol, which relies on browser support for third-party cookies.

Solution

To fix the TidyUp launch error, follow these steps to enable third-party cookies in your browser:

Google Chrome

1. Open Chrome and select the three dots (⋮) in the top-right corner

2. Select Settings

3. From the left sidebar, select Privacy and security

4. Select Cookies and other site data

5. Choose Allow all cookies

Mozilla Firefox

1. Open Firefox and select the three lines (☰) in the top-right corner

2. Select Settings (or Preferences on some systems)

3. Go to the Privacy & Security panel

4. Under Browser Privacy, choose Standard

   • Or select Custom and ensure Cookies is not set to “All third-party cookies”

Safari (Mac)

1. Open Safari and select Safari in the top-left corner of your screen

2. Choose Settings (or Preferences in older versions)

3. Go to the Privacy tab

4. Uncheck Prevent cross-site tracking

5. Uncheck Block all cookies

Now you should be able to open TidyUp in Canvas without encountering the OIDC flow error.

Root Cause

When third-party cookies are blocked in a browser, it interferes with the OIDC (OpenID Connect) authentication flow required by LTI 1.3 tools like TidyUp. Because the session data cannot be shared correctly, the authentication fails, resulting in a fatal error and preventing the tool from launching.

Still need help? Reach out to the Technology & Learning Program for further assistance.