Lock then run the Promise only in one window/tab with Web Locks API (native/polyfill).

lockThenRun.ts

if (!window.isSecureContext) import("navigator.locks");

async function lockThenRun<T>(name: string, callback: (lock: Lock | null) => Promise<T>) {
  return await window.navigator.locks
    .request(name, { ifAvailable: true }, async (lock) => {
      if (lock === null) throw new DOMException("The lock was not granted.");
      await new Promise((resolve) => setTimeout(resolve, Math.random() * 100));
      return lock;
    })
    .then(callback)
    .catch(() => null);
}