[Bug]: preview doesn't work for Customer account UI extensions

[DawidKopys]

Please confirm that you have:

• Searched existing issues to see if your issue is a duplicate. (If you’ve found a duplicate issue, feel free to add additional information in a comment on it.)
• Reproduced the issue in the latest CLI version.

In which of these areas are you experiencing a problem?

App

Expected behavior

Preview with shopify app dev should work for customer account ui extensions.

Actual behavior

Endless loader when trying to preview an extension with target in the customer area.

Verbose output

Verbose output

Paste the output here!

Reproduction steps

1. Setup a simple extension only app with one "checkout ui extension" (you can follow this guide from shopify dev docs)
2. Run shopify app dev
3. Open UI Extension DevConsole, you can do it by pressing p in the terminal with shopify app dev running.
4. Click on a preview link for the customer ui extension target.

Result: endless loader, customer page is not displayed, there are no visible errors.

More context: I am trying to preview this app on a sandbox store with new customer accounts enabled - this one: https://creativestyle-sandbox.myshopify.com/

Operating System

Mac OS Sonoma 14.6.1 (23G93)

Shopify CLI version (shopify --version)

3.76.0

Shell

iTerm2

Node version (run node -v if you're not sure)

v20.18.0

What language and version are you using in your application?

JavaScript React