Worklet

• cheaply passing binary data to worklets, and the implications on P&V and TypedOM
• #872: Supporting postMessage on worklets
• #869 [css-animationworklet] Sending data to animators in worklet from main thread (here since it is closely related to the above)

Paint

• #877: [css-paint-api] Cycle possible using inputProperties()
• #899: [css-typed-om] Opaque font P&V type for PaintWorklet font rendering.

Layout

• #844: Unregistered layout function and blockification
• #898: Design to allow for more layout engine optimizations

Animation

• #850: Avoid StatefulAnimatior/StatelessAnimator superclass and use existence of state() function

Proposals for new specs

• #857 Custom functions for modifying CSS values