Last verified 2026-07-14
shopify checkout extensibility custom field broken
Checkout extensibility apps can brick Plus checkout after a theme or app change. Isolate the last install, then re-test the full path.
The actual problem
Checkout UI extensions fail silently after a theme or app update and kill conversion on paid traffic.
Do this
- Reproduce checkout on mobile + desktop with a real payment method in test mode.
- Checkout editor → disable custom extensions one by one until the error clears.
- Check app changelogs for checkout extensibility breaking changes this week.
- Re-enable only the extension that is load-bearing; leave experiments off paid campaigns.
Tools for this job
- Tillkiln
Finds related checkout traps (guest, OOS, stacking) in the same pass
Scan the live storefront for stacking, OOS-buyable, and dead links before you blame ads → tillkiln.com.
Related intents
Scan the store before more ad spend
Tillkiln finds checkout and storefront leaks — stacking discounts, OOS still buyable, dead collection links — with a rough $ leak estimate.
Also from Cashkiln
- Tillkiln — scan checkout leaks before you buy more ads
- Netkiln sample — client-ready revenue-health page from a payouts CSV ($19 clean unlock)
- Free leak checklist — six operator checks
Deep-dive report — $29
Self-serve checklist expansion for this query family. PayPal Checkout. No call.