Shopify has set a hard deadline: on August 26, 2026 the Additional Scripts box (Settings → Checkout → Order status page) stops executing on every store that is not on Shopify Plus. This is part of the upgrade of the Thank You and Order Status pages to Checkout Extensibility.
What exactly breaks
Everything pasted into Additional Scripts simply stops running. The most common casualties:
- Google Ads conversion tags — your campaigns keep spending, but conversions stop being recorded, so Smart Bidding starts optimizing blind.
- Meta (Facebook) pixel purchase events.
- TikTok, Pinterest, Snapchat pixels added by hand rather than via official apps.
- Affiliate network postbacks (Impact, Awin, ShareASale, CJ) — affiliates stop getting credited, partnerships quietly die.
- Google Tag Manager containers injected into the order status page.
- Custom JavaScript — surveys, referral widgets, custom analytics.
Why you won't notice
This is the dangerous part: there is no error message. Checkout keeps working, orders keep coming, dashboards keep rendering. The scripts just silently stop firing. Most merchants discover the problem weeks later when ROAS craters or an affiliate partner asks why commissions stopped.
The migration path: Custom Pixels
Shopify's replacement is the Custom Pixel (Settings → Customer events). Custom Pixels run in a sandboxed environment and subscribe to standardized events like checkout_completed. The catch: the sandbox is not the old checkout page.
- No DOM access —
document.querySelector, injected widgets and anything reading the page will not work. - No Liquid — variables like
{{ checkout.total_price }}must be replaced with fields from the event payload, e.g.event.data.checkout.totalPrice.amount. - Different money format — Liquid gave you cents or formatted strings; the pixel payload gives you a decimal amount plus a currency code.
Step-by-step plan
- Inventory. Copy everything out of Additional Scripts. Most stores accumulate 2–6 different trackers there over the years.
- Convert each tracker. Either rewrite by hand against the Customer Events API, or paste the whole script into PixelWard — it detects every tracker, extracts your IDs and generates sandbox-ready Custom Pixel code.
- Add pixels. Settings → Customer events → Add custom pixel, paste, connect.
- Verify. Place a test order and confirm events arrive in each ad platform.
- Delete the legacy script so nothing double-fires while both systems run.
- Monitor. A migrated pixel can still break later — theme changes, consent updates, app conflicts. Set up monitoring so silence becomes an alert instead of a surprise.
Do this before August, not in August
Ad platforms need clean conversion data continuously; even a two-week gap degrades bidding algorithms. Migrating now costs an afternoon. Migrating after the shutoff costs the gap plus however long you didn't notice.