Can blocking the call stack delay setTimeout callbacks in JavaScript?
Yes. If synchronous code is still running, the callback stays in the queue. The event loop cannot push it to the stack until the stack is empty. A 5-second blocking function delays all queued timers by 5 seconds.
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More FAQs in How setTimeout Works Behind the Scenes in JavaScript
It hands the timer to a Web API, continues running synchronous code, and when the timer fires, pushes the callback to the macrotask queue. The event loop runs the callback only when the call stack is empty and microtasks are done.
No. The callback goes to the macrotask queue. The event loop runs it only after the current call stack is empty and all microtasks are done. So it runs after synchronous code.
Because promise callbacks go to the microtask queue, which the event loop drains completely before touching the macrotask queue where setTimeout callbacks live. Microtasks always run before macrotasks.
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