Developers often encounter a frustrating issue: users lose unsaved data when JWT tokens expire and the app redirects to the login screen. This happens because the frontend typically redirects on a 401 Unauthorized error, discarding the user's progress. The solution lies in handling 401 errors more gracefully, preserving user input and enhancing the overall user experience.

To address this, developers can implement a resilience pattern. This involves intercepting 401 errors, queuing the failed request, and refreshing the token in the background. By doing so, the app can retry the original request with a new token, ensuring that the user's data is saved without interruption. This approach is particularly crucial for forms, comments, and settings where user input is at stake.

Testing this pattern can be challenging due to the natural expiration time of access tokens, often set to one hour. To overcome this, developers can use tools like Playwright to simulate token expiration by intercepting requests and stripping the Authorization header. This forces the backend to return a 401 error, allowing developers to verify that their app's recovery logic works as intended.

By adopting this strategy, developers can build more resilient and user-friendly applications. It's a shift from treating 401 errors as fatal to viewing them as recoverable, ultimately leading to a better user experience and more robust software.