In six days Shopify auto-upgrades the Thank You and Order status pages on every non-Plus store. The Additional Scripts field goes with it. Whatever is sitting in there right now (the Google Ads conversion tag, the Meta pixel, a GTM container, that one script somebody pasted in 2022 and never documented) stops running on 26 August. It is not migrated. It is removed.

Plus stores went through this in August 2025. Non-Plus stores are next, and the deadline applies to every store regardless of size or revenue. If you inherited a Shopify build from an agency or a previous developer, there is a decent chance nobody on your team has opened that field in two years.

The failure is silent, and that is the actual risk

Nothing crashes on the 26th. Checkout still loads. Orders still land. No 500s, no alerts, no angry customer emails.

What dies is measurement. Google Ads stops receiving conversion signals, so Smart Bidding keeps spending while optimising against nothing. Meta attribution quietly collapses and the traffic reallocates itself to "direct" in your reports. Post-purchase survey scripts stop firing. Any custom logic you had on the order status page for COD confirmation, referral tracking, or loyalty enrolment just stops.

Bidding algorithms need a week or two of conversion data to stabilise. So the realistic sequence is: tracking dies Wednesday, nobody notices because revenue in Shopify admin looks normal, and two weeks later someone asks why ROAS fell off a cliff. By then you have burned a fortnight of ad budget on a model bidding blind, and you have a hole in your analytics history you cannot backfill.

What replaces what

The replacements exist and they are better. They are just not automatic.

Additional Scripts becomes a custom Web Pixel in Settings > Customer Events, subscribing to the checkout_completed event
Custom content on the Thank You page becomes a Thank You page checkout UI extension
Order status page customisations become Order Status extensions
App-injected script tags are the app vendor's job, but you still have to verify each one. Some need a toggle flipped, some need a reinstall, and some apps have quietly gone unmaintained

One catch worth knowing before you start: web pixels run in a sandboxed iframe. No DOM access, no jQuery, no reading values off the confirmation page. If your old script scraped the page for an order total or a customer email, that logic has to be rewritten against the event payload instead. Budget an hour for that, not five minutes.

Do this before the weekend

Open Settings > Checkout, screenshot the Additional Scripts field, and paste the raw code into a doc. That doc is your inventory and your rollback reference.
Sort every snippet into three buckets: still needed, dead weight, owned by an app.
Rebuild the "still needed" ones as custom pixels. Most stores have two or three that genuinely matter.
Place a real test order. Then confirm the event actually arrived in GA4 realtime, Meta Events Manager, and Google Ads conversion diagnostics. Do not trust the pixel editor's preview alone.
Annotate the switchover date in your analytics tool so the step change in your data has an explanation attached to it six months from now.

The teams that get hurt here will not be the ones who decided to skip the migration. They will be the ones who assumed a platform upgrade means the platform moves your code for you. It does not, and Shopify has been clear about that.

Deprecation deadlines are a good forcing function for an audit you were putting off anyway. Go read what is actually in that field. You will probably find something you can delete.

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