After finishing our first milestone of retained rendering (#21756), let's explore what more we can achieve with retained rendering. Here are some examples:

• Explore PhysicalShapeLayer in Fuchsia: Retained rendering in Fuchsia PhysicalShapeLayer engine#6558
• Explore if we can add an option to RepaintBoundary and improve performance significantly by using snapshot of a layer subtree that's not a child of an OpacityLayer. See Add RasterCache option to RepaintBoundary widget #32662.