layoutId shared transitions across React Router route boundaries

Shared Layout Animations and Mount Timing

Framer Motion uses the layoutId prop to coordinate shared element transitions between different components. For this mechanism to function, the library requires both the exiting component and the entering component to be mounted in the DOM during the same render pass to calculate the transition delta.

Router Integration Constraints

Standard React routing patterns typically unmount the current route's component before mounting the next. This behavior creates a timing mismatch where the source element is removed from the DOM before the target element exists, causing layoutId transitions to fail or fall back to standard layout animations.

While AnimatePresence with mode="popLayout" can mitigate some unmounting issues, there is no documented first-class API for managing layout measurement handoffs across disparate route boundaries in Framer Motion 11+.

• How can a developer ensure simultaneous mount timing for layoutId elements when using a router that enforces strict unmount-before-mount cycles?
• Is there a supported configuration to persist layout measurements across route transitions without relying on custom router wrappers?