Did microcontainers ensure data exchange between each other without intermediaries?

Yes, micro frontends can exchange data directly without intermediaries, using, for example, browser events (Custom Events) or shared objects in the global scope (window). This approach reduces latency and complexity but requires careful management of dependencies and isolation to avoid conflicts.

Example of data exchange via events:

// In one micro frontend
window.dispatchEvent(new CustomEvent('userLoggedIn', { detail: { userId: 123 }}));

// In another micro frontend
window.addEventListener('userLoggedIn', event => {
  console.log('User logged in:', event.detail.userId);
});

However, intermediaries (such as global state or event bus) are often used to better control interaction and scalability.