Hi there,
After upgrading our admin.order-details.action.render extension from 2025-10 to 2026-10 (SDK 2026.10.2), attachment uploads fail immediately in Chrome with “TypeError: Failed to fetch”.
Files come from s-drop-zone and are submitted using FormData + fetch. Even tiny images fail. The same uploads work in Firefox, and requests without attachments work in Chrome.
DevTools pauses inside Shopify’s extension worker at:
r.body = yield e.arrayBuffer()
This is before the request is forwarded to the host. Our upload code hasn’t changed.
Has anyone seen this? Could it be a Chrome-specific regression in the extension runtime?
Thanks