Pi 1.0 changes terminal defaults and MCP credential ownership

The new default is fullscreen; tuiMode: "regular" preserves normal scrollback. MCP OAuth now checks the authorization-response issuer and stores credentials by server name and URL; old URL-only credentials move to the first server that uses them. Verify the signed-in account for each configured server after upgrading. ⁴

Relevant to: Pi users with terminal preferences or multiple MCP identities.