`svelte` is an invalid ES Module

[tanhauhau]

Describe the bug

From webpack/webpack#11875

node node_modules/svelte/index.mjs
Error [ERR_UNSUPPORTED_DIR_IMPORT]: Directory import '/home/evilebottnawi/IdeaProjects/copy-webpack-plugin/node_modules/svelte/internal' is not supported resolving ES modules imported from /path/to/node_modules/svelte/index.mjs
    at finalizeResolution (internal/modules/esm/resolve.js:267:17)
    at moduleResolve (internal/modules/esm/resolve.js:668:10)
    at Loader.defaultResolve [as _resolve] (internal/modules/esm/resolve.js:758:11)
    at Loader.resolve (internal/modules/esm/loader.js:100:40)
    at Loader.getModuleJob (internal/modules/esm/loader.js:246:28)
    at ModuleWrap.<anonymous> (internal/modules/esm/module_job.js:47:40)
    at link (internal/modules/esm/module_job.js:46:36) {
  code: 'ERR_UNSUPPORTED_DIR_IMPORT',
  url: 'file:///home/evilebottnawi/IdeaProjects/copy-webpack-plugin/node_modules/svelte/internal'
}

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Expected behavior
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Information about your Svelte project:

• Your browser and the version: (e.x. Chrome 52.1, Firefox 48.0, IE 10)

• Your operating system: (e.x. OS X 10, Ubuntu Linux 19.10, Windows XP, etc)

• Svelte version (Please check you can reproduce the issue with the latest release!)

• Whether your project uses Webpack or Rollup

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[WofWca]

Related #5003

[Conduitry]

The imports in the published package should now be fixed in 3.29.5.