Quick answer
When FBT add-ons do not appear, the product is usually not a trigger, the offer is inactive, unavailable add-ons are hidden, or coexistence rules hide FBT because a fixed kit inline widget is present.
- FBT lives on trigger PDPs only.
- Fixed kit on same page may hide FBT by default.
- All add-ons OOS + hide unavailable = empty widget.
- Readiness errors prevent activation entirely.
Readiness rules that block publish
Trigger cannot equal add-on variant. Duplicate add-on variants fail readiness. Fix in editor before expecting storefront output.
- trigger_addon rule
- duplicate_addons rule
Display styles
checkbox_list, product_cards, and compact_rows change layout but not eligibility. Switch styles if shoppers miss add-ons on mobile.
Final recommendation
Confirm trigger mapping and coexistence before redesigning the offer. Most missing FBT cases are configuration, not theme conflicts.
If you want this kind of offer to feel native to the buying journey, Kitforge Bundles is built around that exact problem: turning related Shopify products into clearer bundle offers before the shopper reaches checkout.
FAQ
Can one product be both trigger and add-on?
Not for the same offer — readiness blocks trigger variants from appearing as add-ons.