IE10 error (const) only after deploying, not during dev


Hi guys!

So here I am again with a stupid IE10/babel error.

When I connect to my localhost during development with an IE10 all is working fine, but after a deployment the whole page is dead on IE10 due to a const declaration which was not “babel’fied” to a var.

I am currently in my master branch still using I tried several versions of my devDependencies- meaning I removed some of them, even completely also removed my .babelrc … it all stays the same - working during dev, dead after deployment.

  "devDependencies": {
    "babel-plugin-import": "^1.6.3",
    "babel-plugin-transform-class-properties": "^6.24.1",
    "babel-preset-meteor": "^6.22.0",
    "babel-preset-stage-2": "^6.22.0",
    "chimp": "^0.41.2"

Can someone help? I just don’t understand why this is working in dev but dead after deployment.

EDIT: I also tried running it with the --production flag (prior I removed the force-ssl package so I can visit the page on localhost without ssl) - all working fine on IE10, no problems. isn’t the --production flag pretty much exactly the same what happens on the server after deployment?

It seems like completely deleting the docker container prior to deployment fixes this problem. Does anyone have any idea why? maybe some npm 5 problems with caching newer versions of packages and not re-downloading the old ones or something like that?!

God I hate errors like that … 3 hrs wasted with some BS … :roll_eyes: :expressionless:


I don’t think this will solve your issue, but I strongly recommend against having babel-preset-meteor installed via npm, along with any other babel plugins that Meteor automatically installs and uses via the ecmascript package.
It’s a frequent source of issues because of conflicts with the version that Meteor wants to use