Blank Screen on IE11/Edge

Hi everyone,

Our app is having a full blank screen on IE11 and Edge. I don’t have a great understanding of how babel is used in meteor (1.11.1) and how the compiling works but clearly there is some code that is not readable for these browsers.

We have

es5-shim@4.8.0 # ECMAScript 5 compatibility for older browsers
ecmascript@0.14.3 # Enable ECMAScript2015+ syntax in app code

in the packages.

Error says ‘(’ is missing and it seems to come from a package we use (and we need) but also getting errors such as:

Unable to get the property 'meteorInstall' a null reference or undefined

Also we have an error in the modules.js file at this line:

levels: function* levels(editor)

saying that a ‘(’ is expected…

Tried to add polyfill in header, add npm modules… and nothing worked so far. Any idea or lead is welcomed. Thanks in advance.

Any idea how we could add more config / polyfills to make this work ? Thanks a lot

A simple way to reproduce:

meteor create --react meteor-app
cd meteor-app
meteor npm install --save slate slate-react

Change App.js to the following:

import React, { useMemo, useState } from "react";
import { createEditor } from "slate";
import { Slate, withReact } from "slate-react";

export const App = () => {
  const editor = useMemo(() => withReact(createEditor()), []);
  const [value, setValue] = useState([]);

  return (
        onChange={(newValue) => setValue(newValue)}

and you can try to run the app on IE11 but it won’t work
I tried the following package.json extra config:

  "meteor": {
    "mainModule": {
      "client": "./client/main.js",
      "server": "./server/main.js"
    "nodeModules": {
      "recompile": {
        "slate": "legacy",
        "slate-react": "legacy"

but didn’t work