Have you ever had a bug where things were happening in the wrong order, or particular style changes were being ignored? Ever fixed that bug by wrapping a section of code in a setTimeout? Ever found that fix to be unreliable, and played around with the timeout number until it kinda almost always worked?

This talk looks at the browser’s event loop, the thing that orchestrates the main thread of the browser, which includes JavaScript, events, and rendering. We’ll look at the difference between tasks, microtasks, requestAnimationFrame, and where events land.

Hopefully you’ll never have to use setTimeout hacks again!

Special thanks to CSS Wizardry, Leeds International Festival, and Stac for supporting this talk.