function ErrorBoundary() {
  const error = useRouteError();
  console.error(error);
  return <div>{error.message}</div>;
}

<Route
  errorElement={<ErrorBoundary />}
  loader={() => {
    // unexpected errors in loaders/actions
    something.that.breaks();
  }}
  action={() => {
    // stuff you throw on purpose in loaders/actions
    throw new Response("Bad Request", { status: 400 });
  }}
  element={
    // and errors thrown while rendering
    <div>{breaks.while.rendering}</div>
  }
/>;