What changed, with the dates
Shopify replaced the old Thank you and Order status pages, and the customizations on them have to be rebuilt. Here's what its help center and developer docs say (checked November 2026):
- August 28, 2025: Shopify Plus stores lost script tags on these pages, along with checkout.liquid and additional scripts. Shopify also says the additional scripts section in Checkout settings has been view-only since that date.
- August 26, 2026: the upgrade deadline for non-Plus stores. Script tags stop running on the Order status page for these stores. Shopify simply ignores them, so you don't have to delete them.
- March 1, 2027: script tags stop running on storefront pages too. If an old app still loads this way, ask its developer what the plan is.
- The upgrade is required if you used incompatible apps, scripts or pixels. Your personalized upgrade guide is in the Shopify admin, and it groups your scripts by purpose.
What stopped, and what didn't
Anything pasted into Additional Scripts or loaded by a script tag on the old pages is affected. Common examples: fbq() and gtag() purchase code, TikTok and Pinterest tags, affiliate conversion tags, post-purchase surveys and session recording.
Pixels added through an app or under Settings, Customer events aren't affected, because the new pages support them. So you can have a store where one pixel carries on and a second one, in Additional Scripts, has stopped.
A warning about reading your own numbers. In the Shopify Community, merchants compared notes after August 26 and several reported pixels going quiet with no error, with Meta showing fewer purchases than Shopify on some stores but not all. One useful point from that thread: if a server event still arrives, the total can look nearly normal even though the browser event has gone. So check the source of each event, not only the total.
How to find what you lost
Do this before you change anything, so you have a list to work from.
- Open Settings, Checkout and, if your store still shows the Additional scripts section, copy everything in it into a document. It's view-only, but you can still read it.
- Open your personalized upgrade guide in the admin and go through the scripts it found.
- Sort each script into one of three groups: conversion tracking (fbq, gtag, dataLayer.push, ttq), something the buyer sees (survey, referral offer, upsell), or a third-party tag (affiliate, attribution, session recording).
- Look in Settings, Customer events for pixels that already cover the same platform, so you don't add it twice.
- Compare your orders with Purchase events by day, from a few weeks before your upgrade until now. In Meta Events Manager, look at browser and server events separately.
How to rebuild it
Each group has a different replacement. The upgrade guide also lets you deactivate a script instead of replacing it, which is the right call for old tags you no longer use.
- Conversion tracking: use the platform's own app or a tracking app, or write a custom pixel that subscribes to checkout_completed. Shopify's custom pixels run in a sandbox, so old code doesn't always work unchanged.
- Things the buyer sees: use an app block in the checkout and accounts editor. If the app isn't in the list of blocks, it probably hasn't been rebuilt for the new pages, so ask the developer or look for a replacement.
- Affiliate and other third-party tags: ask the vendor for their current Shopify setup. Many need an app pixel or a custom pixel now.
- Your own custom events: Shopify's migration guide replaces old event code with Shopify.analytics.publish(), and your custom pixel then subscribes to that event.
Connect first or remove first?
Shopify's pixel migration guide names the trade-off. Connect the new pixel before you remove the old code and you minimize missed events, but you may count some twice for a while. Remove the old code first and you avoid duplicates, but you may miss events in between.
If the old code has already stopped running on your Thank you page, that choice is mostly made for you. Still look for leftovers in theme.liquid: the base code of the old pixel often sits in your header, and Shopify advises removing it, or changing it, when your new pixel handles the same events.
Why a new pixel isn't the whole fix
Moving to a custom pixel gets you working again, but it's still browser tracking. Shopify's documentation says checkout_completed fires once per checkout, typically on the Thank you page, and that it doesn't fire if that page fails to load. With an upsell in between, it fires on the first upsell offer page instead, and not again on the Thank you page.
So a buyer who closes the tab, doesn't come back from a redirect, or blocks scripts still goes unreported. That's why it's worth sending the purchase from the order itself as well. Settl does that: Shopify tells Settl the moment an order is paid, and an hourly check picks up anything that slipped through. The purchase goes server-side to Meta, TikTok, Google (GA4 and Google Ads), Snapchat, Pinterest, X, Microsoft Advertising and Reddit, with the saved ad click and the same event id as the browser, so each platform counts it once.
What Settl doesn't replace: surveys, referral offers, affiliate tags and session recording. Those still need their own app block or pixel. And sales that were never reported during the gap won't show up again on their own, so note the dates and keep them out of your campaign comparisons.