The Multiple Browser Tab Token Trap: Synchronizing JWT Refresh Across Browser Tabs

How multiple open browser tabs can accidentally DDOS your auth server, and how to fix it with the Web Locks API. Picture this: You’ve just shipped a state-of-the-art Axios response interceptor. You implemented a mutex lock (isRefreshing) and a promise queue (failedQueue) to handle concurrent 401 errors. You tested it within a single tab, and it worked like a charm. You gave yourself a high-five and closed your laptop. Then, a power user logs in. Like most humans on the internet, they don't use j