How is this attachment made?

1. Local HTML page with JavaScript physics engine (matter.js)
2. HTML elements and CSS animation for text
3. ScreenFlow video capture of Safari on Retina display (cut to 2400×1260)
4. Export as 50% size 60fps H.264 3,000kbit multi-pass w/ motion blur

(Safari is by far the smoothest and best browser for this kind of thing, Firefox is second best. Don’t even try Chrome, it’s sad.)

You need to capture in Retina and scale down 50% for the best quality.