Function useTransition

packages/react-reconciler/src/ReactFiberHooks.js:4119–4123

()

      return mountDeferredValue(value, initialValue);
    },
    useTransition(): [boolean, (() => void) => void] {
      currentHookNameInDev = 'useTransition';
      mountHookTypesDev();
      return mountTransition();
    },
    useSyncExternalStore<T>(
      subscribe: (() => void) => () => void,
      getSnapshot: () => T,