Redirect to app page is replacing the page content completlly and not the iframe content only

[Dror-Dromi]

This is an old Shopify App using CURL style calls.

App installation flow

• Authenticate
• approving payment method
• Authenticate again (online) to get the associated user.
• show app setting page

1. GET / - redirect to authentication
2. GET /auth-callback - redirect payment activation
3. REDIRECT payment panel
4. GET /payment-callback - redirectl user auth
5. GET /user-auth-callback - redirect to root
6. GET / 
7. REDIRECT to App setting url

The last redirect couching the problem, The page url is replaced to the app setting page and it appears like the page is stand alone page and not part of Shopify admin page.

Notice that this is happening on installation only. If the application is already installed than everything works fine:

1. GET / - redirect to user auth
2. GET /user-auth-callback - redirect to root
3. GET / 
4. REDIRECT to App setting url