setTimeout(), setInterval(), and requestAnimationFrame()
What happens to setTimeout/setInterval callbacks when JavaScript is executing a long-running synchronous operation?
During long-running synchronous operations: 1) Timer callbacks are queued but cannot execute, 2) Execution occurs only after the call stack is empty, 3) This can cause significant timing irregularities, 4) No parallel execution due to JavaScript's single-threaded nature, 5) Can lead to UI unresponsiveness, 6) May cause callbacks to bunch up and execute in rapid succession after the operation.