Checkout.liquid Deprecation and Script Tags

[AndreaPokoto]

Hi,

I have an App that uses the script tag to inject a script that renders a pop-up and other content inside the shop DOM. That app is mainly used on the shop's pages and rarely on the thank you page.

From the Shop admin > Settings > Checkout, the app is reported incompatible with the new checkout: 
"Apps that currently customize your Thank you and Order status pages".

But from the official docs, I can see these deadlines:

August 13, 2024: Deadline to upgrade your Information, Shipping, and Payment pages.
August 28, 2025: Deadline to upgrade your Thank you and Order status pages, including your apps, using script tags and additional scripts.

QUESTION 1)
Is our deadline for the upgrade August 28, 2025? If so, why is the admin reporting the app as incompatible now? 
This is causing a lot of confusion among our merchants.

QUESTION 2)
Besides moving to "App embed blocks," is there anything else we need to do to make the App compatible,

if we DO NOT WANT to customize the checkout/thank you/order pages? 

QUESTION 3)
While "App embed blocks" work fine to inject scripts into the theme, I understand the new checkout extensibility does not allow manipulating the DOM on the checkout page.

Can we inject our script into the new checkout version of the thank you /order pages?
Since our App design can't be replicated with Checkout UI components, what is the best practice for rendering a popup on the new thank you page?

Thanks in advance for any clarification about these points. I am pretty sure other App Devs are 
facing these doubts.

Best,
Andrea

[Liam]

HI Andrea,

For question 1 - are you seeing any reports in the partner dashboard for your app of any deprecated calls being made? If not and your merchants are still seeing this warning you'll need to connect with partner support directly who can look into why this happening. 

2: If you move to app embed blocks and the app is not affecting the checkout in any way, then it will be compatible with upcoming changes with checkout extensibility.

3: There's no way to inject scripts into the new checkout - I'd recommend looking into Shopify Functions to see how you could use these to replicate your previous checkout customisations. 

Hope this helps!

[AndreaPokoto]

Hi Liam, Thanks for your quick reply. I attached a sample customization report (similar to the one users are getting now)



I investigated the app embed blocks further, and I see they work on the thank you page as well,
so migrating will solve the issue for us because we do not need to target the checkout page.

That said, I think the customization report is quite misleading for merchants:
while script tags will be deprecated next year on the thank you page, it seems like the App is already not compatible with the upcoming checkout.liquid update on Aug, 13th... but you can actually upgrade to the new checkout and the App will still work on the thank you page for another year.

Best,
Andrea