how to import mjs in vscode?

Is it possible to make a vscode extension made of mjs files?

because I tried to make an extension with mjs files only, in order to have full es6 features without TypeScript. But it does not run:

If I make the extension with $ vsce package it does not give any error but it makes an extension that does not work when installed: the contributions that I've put in the package.json are present but vscode shows an error popup that says

Activating extension 'my.ext' failed: Must use import to load ES Module: c:\vsext\extension.mjs.

and every command I try to run gives an error

command 'my.cmd' not found

If I run the extension on the debugger, and the breakpoint on uncaught exception option flagged, it breaks on /src/vs/workbench/api/node/extHostExtensionService.ts:88.

After further search, I noticed that this exception in generatend when the script tries to load the first mjs module.

there is something I can do in order to include my mjs library files?

I think that this behaviour could also impact the use of npm modules with mjs files.

EDIT

Found (kind of) a way using esm:

The idea is to use esm to handle es6 imports and share the vscode object between imported modules

this could seem quite tricky but when I tried to just import * as vscode from "vscode" im my mjs files, vscode complained that can't find module vscode.

so I've done the following

• add 'esm' as dependency
• in all the files where vscode is used, remove the import of vscode and add something like this function

var vscode; // will store vscode obj
export function IMPORTVSCODE(vscodeInstance){
    vscode = vscodeInstance
}

• create a init file where you require vscode (with node native require) and your main module (with esm require)
• in the init file call main.IMPORTVSCODE(vscode)
• on all the files A that imports a file B that need vscode, before use the exported stuff from file B, call B.IMPORTVSCODE(vscode)

for example

// init.js
const vscode = require("vscode")
const esm = require("esm")(module/*, options*/)
const main = esm("./main.mjs")
main.IMPORTVSCODE(vscode)
module.exports = main

// main.js
import * as other from "./other.mjs"
var vscode; // will store vscode obj
export function IMPORTVSCODE(vscodeInstance){
    vscode = vscodeInstance
}
function activate(){
  other.IMPORTVSCODE(vscode)
  other.methodThatNeedsVscode()
}

// other.mjs
var vscode; // will store vscode obj
export function IMPORTVSCODE(vscodeInstance){
    vscode = vscodeInstance
}
export function methodThatNeedsVscode(){
    vscode // ...use vscode
}

My extension runs fine now!

But I think that better ideas could be found, so if somebody has some finest solutions, please share them