v143 · miscellaneous

FedCM-Migration of nonce to params field & Renaming of IdentityCredentialError code attribute to error

Migration of nonce to params Field: The nonce parameter in navigator.credentials.get() is moving from a top-level field to the params object for better API design, extensibility, and maintainability. This structured approach simplifies parsing for Identity Providers, supports future-proofing without versioning, and aligns with modern API patterns. For Relyin

concepts

  1. params Rename

    Interactive migration aid: type your nonce / clientId / configURL and see the before vs after call shape, plus a live probe for the renamed IdentityCredentialError attribute.

  2. Codemod helper

    Paste FedCM client code — the page detects the deprecated nonce top-level field and err.code attribute, rewrites them in place, and reports each change.

  3. Error name explorer

    Catalogue of every IdentityCredentialError.error value, what it means, and the recommended UX response — with a live probe of which attribute (legacy .code or new .error) your browser exposes.

  4. Migration Wizard

    A four-step wizard (Scan → Review → Apply → Verify) that detects top-level nonce and old IdentityCredentialError code names in pasted FedCM client code, shows a side-by-side before/after diff with colour-coded changed lines, outputs migrated code for copying, and runs a live navigator.credentials.get() call with the new format to verify the change.

why it shipped

see https://github.com/w3c-fedid/custom-requests/issues/3 for more discussion on motivation

references