Under the hood
Switching models mid-session now preserves rendered artifact-frame data across the switch
What
When the model used for the main conversation loop changes mid-session, Claude Code now optionally takes a snapshot of the rendered client-side thread-list data before switching. If that data changed, it's passed along as renderedClientData into the bootstrap-refresh step that runs after the switch.
Why
This stops the client's displayed state (such as artifact frames) from being lost or reset when you change models in the middle of a session.