Checkout UI Extension not being launched

[pokerjoker3000]

Hello there,

I have a ui checkout extensibility that works fine in dev. But when I deploy it to production it's not enabled for our customers.

The checkout uses the "purchase.checkout.reductions.render-after" target and deployment works fine. Shopify tells me that a new version with the extension is active.

However I added a console.log("Init my app") to the code and can't see it on the stores.

Any ideas what's not working here?

Thank you very much.

[dev-b]

Same problem, my simple Checkout UI extension-only app works in dev preview but not when actually installed to that same dev store, nor when deployed as a "custom app" to a production ShopifyPlus store. 

No errors, no bad stats in the partner dashboard for the app. Just never seems to even try to load the extension (my debugging console.warn calls also never fire).