Default export is incorrect when imported via dynamic import

[DreierF]

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Describe the bug

When using import('clipboard') to dynamically load the Clipboard.js library, the resulting module looks like the following, with two default fields nested into each other:

in contrast when loading the library with a regular import ClipboardJS from 'clipboard' I directly get the constructor function or similarly with import * as clipboard from 'clipboard' the following object with only a single default field:

I would expect to get the same module shape also via import('clipboard'), which is also what Webpack produces.

Reproduction

Use the vanilla vite template, install clipboard and add the following code snippet to main.js

import('clipboard').then(({default: ClipboardJS})=>{
    new ClipboardJS('h1');
});

This fails with

Uncaught (in promise) TypeError: ClipboardJS is not a constructor
    at main.js:8

System Info

• vite version: 2.0.0-beta.60
• Operating System: MacOS
• Node version: 14.15
• Package manager (npm/yarn/pnpm) and version: yarn