Shopify Checkout Extensibility Migration Checker

It scans the public HTML of any Shopify storefront URL for the migration signals that actually render to the page: inline gtag, raw fbq() outside the noscript fallback, GTM containers, TikTok ttq, Pinterest pintrk, Snapchat snaptr, Impact affiliate pixels, Hotjar and Clarity inline init, Klaviyo onsite, Postscript SDK, Attentive, Triple Whale, Bing UET, Recharge widget, Shop Pay component overrides. It also flags the single reliable storefront-side green flag: Shopify Web Pixels Manager active (which means Customer Events is running and any installed channel app like Google, Meta, TikTok, Pinterest, Snapchat is migration-safe). Verify the specific channel apps in admin at Settings, Customer Events. Each finding maps to the Aug 26 2026 deadline and a fix recommendation. Anything that lives only in admin (Additional Scripts, Order Status scripts, Shopify Scripts, checkout.liquid) cannot be detected from the outside; the tool surfaces those in a separate Admin Verification panel as a checklist with manual verification steps.

On August 26, 2026, Shopify removes Additional Scripts, the Thank You page script box, and Order Status page scripts on Basic, Shopify, and Advanced plans. Anything pasted in those legacy fields stops firing that day. Plus stores already hit their version of this deadline on August 28, 2025. The non-Plus deadline is the second wave and there is no extension on the way (per Shopify's official upgrade guide). If your GA4 tag, Meta pixel, or COD validator lives in a legacy script field, it dies that morning. The full migration plan is in my non-Plus checkout extensibility post.

Plus migration was about checkout.liquid replacement and custom UI extensions. Non-Plus migration is mostly about tracking and validation. Most Basic/Shopify/Advanced merchants never touched checkout.liquid (it required Plus). What they did do is paste tracking scripts into Additional Scripts, build COD validators in JavaScript, and rely on Order Status page scripts for affiliate conversions. That is what dies on August 26. The replacement APIs are the same (Customer Events, Web Pixels, Shopify Functions, Customer Account UI Extensions), but the migration scope is different. This tool ranks findings against the non-Plus playbook.

Tracking goes silent. Conversion data stops flowing into GA4, Meta Ads Manager, TikTok, and any platform whose pixel was pasted as raw code. Validators stop running, so a Cash on Delivery rule that previously blocked $500+ orders will accept them. Affiliate scripts on the Order Status page stop attributing. The store keeps selling because checkout itself does not break. But the analytics and CRO tooling that founders depend on for paid marketing decisions, attribution, and basic accounting goes dark with no rollback. The first sign is usually a marketing manager asking why GA4 conversions dropped to zero overnight.

Anything behind admin-only surfaces. Additional Scripts content, Thank You page scripts, Order Status page scripts, Shopify Scripts (Ruby Script Editor, Plus only), checkout.liquid customizations, Customer Account UI Extensions, Checkout UI Extensions, Shopify Functions, Post-Purchase extensions. None of these render on the public homepage; the storefront-facing scanner has no way to see them. The tool flags those items as a manual checklist in the Admin Verification panel with the exact admin path to open. Treat the public-HTML scan as a triage screen and the admin checklist as the authoritative audit. The Shopify checkout optimization guide covers the deeper migration playbook. If you have admin access, run the official Customizations Report at Settings, Checkout. This tool is the screen for everyone else: agencies, partners, and devs evaluating prospect stores.

It shows days remaining to August 26, 2026. For most non-Plus merchants, the rebuild of any DOM-dependent script (custom GA4 events, COD validators, affiliate scripts) takes two to five weeks of developer time. The countdown reflects realistic project lead time. Merchants starting under 60 days out are in the danger zone for App Store partner availability.

Shopify Scripts deprecate on June 30, 2026, ahead of the broader Aug 26 deadline. The tool surfaces this as a manual admin verification item: the actual Script Editor entries (cart.scripts, line_item.script_discount, shipping_rate.script_discount, payment_gateway.script) live behind the admin and never render in storefront HTML. Open Apps > Script Editor in your Plus admin to inventory rules. Most Plus stores have at least one Script (BOGO, line item discount, shipping rule) that quietly stops working on June 30 if not rebuilt as a Shopify Function. The Shopify Scripts deprecation guide and real examples post walk through the conversion patterns.