Greensock

[leastbad]

I'd love to see how GSAP stacks up against the other three!

https://greensock.com/gsap/

[gnykka]

I haven't used it before, but it will be interesting to try, yes!

[dragoon]

As I understand, GSAP is a an animation engine, you can see on their own comparison page: https://codepen.io/GreenSock/full/DrPzmR. They compare against JQuery 3 (what?), Motion One, Web Animations API, etc.
It can also animate PIXI objects with a Plugin.