Amazingly, this interactive effect works without JS: https://veneer.leftium.com/base/s.13E_wsbrKLEsuV-eDaTKl0a967...

- Falling confetti animation

- Alert with functional close icon

- Dismissing alert also dismisses confetti

- Tabs also work (but unlike example in TFA, requires page load from server...)

- (The page is enhanced with JS; the JS version is smoother and includes fancier confetti)