no copy

// Import one property
import { add } from './mymodule.js';
console.log(add(1, 2));
//> 3

// […]

copy=1:

// Import one property
import { add } from './mymodule.js';
console.log(add(1, 2));
//> 3

// […]

And testing with wider text-content:

no copy

// Declares a function-scoped variable named `x`, and implicitly assigns the
// special value `undefined` to it. Variables without value are automatically
// set to undefined.
// var is generally considered bad practice and let and const are usually preferred.
var x;

// Variables can be manually set to `undefined` like so
let x2 = undefined;

copy=1

// Declares a function-scoped variable named `x`, and implicitly assigns the
// special value `undefined` to it. Variables without value are automatically
// set to undefined.
// var is generally considered bad practice and let and const are usually preferred.
var x;

// Variables can be manually set to `undefined` like so
let x2 = undefined;