There is a problem with the app block. Contact the app developer.

Retired Boards Appdev Extensions

Topic summary

Developers are experiencing an error when using deep linking to add theme app extension blocks: “There is a problem with the app block. Contact the app developer.” The issue appears inconsistently and has specific triggers.

Key findings:

  • Error occurs primarily when installing blocks on new themes (not previously used themes)
  • The problem may involve using incorrect extension UUIDs for different environments (staging vs. production)
  • Deep links redirect users to the wrong page (e.g., Home page instead of Product page)

Workarounds identified:

  1. UUID retrieval method: Add the extension via theme editor, access the theme’s code editor, open the relevant template file (e.g., templates/product.json), and extract the correct UUID from the markup
  2. Cookie permissions fix: Enable third-party cookies for admin.shopify.com in browser settings (Safari, Chrome, Firefox). One user confirmed this resolved their issue completely.

Status:

  • Shopify team (Liam) acknowledged the issue and is investigating
  • No official fix available yet
  • Multiple merchants are reporting the problem, causing frustration for app developers
Summarized with AI on November 5. AI used: claude-sonnet-4-5-20250929.
31

Well it turns out I just had a customer emailing me the same error message when trying to add my App to her Theme via Deeplink.

I am not able to replicate the Problem, not even when using the Theme she uses,

I will keep an eye on this.