Event Loop & Microtasks

How are MessageChannel messages handled in the event loop?

const channel = new MessageChannel();
channel.port1.onmessage = () => console.log('Port 1');
channel.port2.onmessage = () => console.log('Port 2');

Promise.resolve().then(() => console.log('Promise'));
channel.port2.postMessage('');

As synchronous operations
As microtasks
As macrotasks
MessageChannel communication is handled as macrotasks: 1) Message events are queued as macrotasks, 2) Execute after all microtasks are completed, 3) Similar priority to setTimeout and setInterval, 4) Useful for breaking up long computations, 5) Allows UI updates between messages, 6) Important for implementing worker communication patterns.
As high-priority interrupts

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