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)