(UE) Mondial Relay > Checkout > Mobile bug

Technical Q&A
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TL;DR: On mobile checkout, the Mondial Relay official app’s pickup point popup has an oversized top padding that pushes the confirm button out of view — customers can’t validate their pickup point and drop off. This lives inside a locked checkout iframe, so merchants/developers can’t fix it themselves. Only Mondial Relay or Shopify can patch this at the source.

Hi everyone,

I’d like to flag a bug I found while auditing a Shopify store, affecting the official Mondial Relay app on mobile checkout.

Issue
When a customer selects a Mondial Relay pickup point on mobile (available in France or UE market), the confirmation button (“choose this pickup point”) gets pushed below the visible area of the popup. This is caused by an oversized top padding reserved for the close icon — when the pickup point name is a bit long, the popup grows in height and the button ends up hidden, with no scroll indicator to warn the customer. On some configurations there’s no fallback dropdown either, so the customer has no way to complete the selection.

Steps to reproduce

  1. Add a product to cart on a Shopify store (FR/BE market) using the official Mondial Relay app for shipping.
  2. Go to checkout on a mobile device (or a mobile viewport).
  3. Select Mondial Relay as the shipping method and open the pickup point map/popup.
  4. Select a pickup point with a moderately long name.
  5. Try to tap the confirm/select button.

Expected result
The confirm button stays visible and tappable right after selecting a pickup point.

Actual result
The button is pushed out of view because of the excessive top padding. Depending on the store, there’s either no visible cue to scroll, or no button shown at all once the popup height exceeds a certain threshold.

Why it matters
This happens inside the Shopify checkout, in an iframe controlled by the Mondial Relay app — merchants, developers and agencies have no way to fix this from the store or theme side. Only Mondial Relay (or Shopify, depending on where the fix should live) can patch it, which is why I’m raising it here for visibility rather than filing it as a one-off support ticket.

I recorded a short video showing the bug live: https://youtu.be/UCL3meV8_JQ

Suggested fix

  • Increase the popup width so longer pickup point names don’t force extra height
  • Make the “select this pickup point” button full-width / single line
  • Reduce the reserved top padding so it doesn’t push the button out of view

Mondial Relay is used by a large number of Shopify merchants (mainly France, Belgium, Switzerland), so this is likely causing checkout drop-off at scale without merchants noticing, since it won’t show up clearly in standard analytics.

Happy to share more screen recordings or technical details if that’s useful. Flagging this so the Shopify and Mondial Relay teams can take a look.

Thanks,
Mehdi — Founder, ROOTY (Conversion & Tracking Agency for DTC)

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Before this goes anywhere, worth pinning down who actually draws that popup, because your conclusion changes depending on the answer.

The official Mondial Relay app is a public App Store app, and public apps cannot use the Pickup Point Delivery Option Generator API. The docs are blunt about it, only custom apps installed on development stores or on Shopify Plus stores have access, public apps in the App Store and custom apps on non Plus stores do not. So unless the store you audited is Plus running a custom app, Mondial Relay is not the thing rendering that map. Shopify’s own picker is.

You can settle it on one test order. Push an order through the broken flow, open it in admin, and watch the network tab for the fulfillmentOrders payload. There is a pickupPoint object in there carrying a fromDeliveryOptionGenerator boolean. False means Shopify’s native picker placed the point. I saw that exact shape on another thread here a few days ago, carrierCode mondial_relay with fromDeliveryOptionGenerator false, so the combination definitely happens in the wild. That field only exists in the admin payload, it is not on DeliveryMethod in the GraphQL Admin API, so the network tab is the only way to read it from outside.

If it comes back false then sending this to Mondial Relay support is a dead end and it has to go to Shopify with the order attached.

One thing to put in the report either way. The trigger is the length of the pickup point name, not the device. Whoever picks this up to reproduce will tap the first locker in the list, get a short name, see a button that works fine, and close it. Name the exact point that breaks it and the viewport height you saw it at.

Was the store on a standard plan or Plus?