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# Financial Connections Deployment Checklist

This document outlines the essential steps and considerations before deploying your Stripe Financial Connections integration. Following this checklist will help ensure a smooth authentication flow for your users and a robust integration.

## Prerequisites

Before proceeding with deployment, ensure you have a thorough understanding of the Financial Connections integration process. This includes:

*   **Completed Financial Connections Registration:** For live mode, your Financial Connections registration must be complete. You can check its status in your Stripe Dashboard settings. Test data is always available for development and testing.
*   **Understanding Webhook Events:** Familiarize yourself with Financial Connections Account webhook events to effectively receive updates about changes to connected accounts.

## Deployment Checklist Items

### 1. Cross-Origin-Opener-Policy (COOP) Response Header

*   **Configuration:** Configure the page that launches the Financial Connections authentication flow.
*   **Required Setting:** The `Cross-Origin-Opener-Policy` response header must be set to `same-origin-allow-popups`, `restrict-properties`, or `unsafe-none`.
*   **Impact of Restrictive Values:** Using a restrictive value like `same-origin` might interfere with OAuth bank login flows.
*   **Default Behavior:** If your page does not explicitly set a `Cross-Origin-Opener-Policy` header, it defaults to `unsafe-none`.

### 2. Referrer-Policy Response Header

*   **Configuration:** Configure the page that launches the authentication flow.
*   **Required Setting:** The referrer policy should send a `Referer` header to other origins. This can be achieved by either:
    *   Not sending a `Referrer-Policy` response header at all.
    *   Using a value such as `origin`, `origin-when-cross-origin`, `strict-origin`, or `strict-origin-when-cross-origin`.
*   **Impact of `no-referrer`:** Using `no-referrer` suppresses the `Referer` header and can interfere with OAuth bank login flows.
*   **Meta Tag Configuration:** If your page contains a `<meta name="referrer" />` tag, ensure its `content` value is set to one of the allowed policies (`origin`, `origin-when-cross-origin`, `strict-origin`, or `strict-origin-when-cross-origin`).

### 3. iframe Sandbox Properties

*   **Context:** This applies if the page launching the authentication flow is displayed within an iframe.
*   **Required Setting:** Include `allow-popups-to-escape-sandbox` in the `sandbox` property of the iframe.
*   **Reasoning:** Some OAuth flows do not function correctly within a sandboxed iframe. Using `allow-popups-to-escape-sandbox` provides the necessary permissions for these flows to operate.

## Additional Considerations

*   **Testing:** Thoroughly test your integration in a staging environment before deploying to production. Utilize Stripe's test mode and test financial institutions.
*   **Error Handling:** Implement robust error handling to gracefully manage potential issues during the authentication process.
*   **User Communication:** Clearly communicate with your users about the data being accessed and the purpose of the Financial Connections integration.
*   **Security:** Ensure all sensitive data is handled securely and in compliance with relevant regulations.
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