preload-lazy.js

const preloadLazy = (dynamicImport) => {
  let promise;
  function load() {
    if(!promise) {
      promise = dynamicImport();
    }
    return promise;
  }
  
  const component = React.lazy(load);
  component.preload = load;
  return component;
}

const MyComponent = preloadLazy(() => import('../MyComponent'));
// MyComponent.preload()