Pasting still failed because the panel is a nonactivating panel: it can
be key while the app is not active, and menu key equivalents are not
delivered reliably in that state. Cmd+V is now dispatched to the
responder chain directly, and the app no longer replaces SwiftUI's main
menu — it only adds Hide Panel to it, so the Edit items that AppKit
routes text shortcuts through stay intact.
Rows also gained a checkbox so a workspace works as a checklist without
turning the row into a button, which would swallow the checkbox's clicks.