Maximum Call Stack Exceeded

I’m sorry to bother everyone - this may be a dumb question. I’m using Mobx in a Meteor 1.7 project without any issues. I created a brand new Meteor 1.8 project w/React. It only has one route (react router) that works fine. I now want to add a store to begin building the UI. I added mobx and mobx-react using npm install --save. All goes well. But when I try to import { observable } from "mobx"; I get this Stack Exceeded error:

modules-runtime.js?hash=d3c3e5d67c95f97a60888bda7373292efad3be5e:56 Uncaught RangeError:
Maximum call stack size exceeded
    at Object.hasOwnProperty (<anonymous>)
    at strictHasOwn (modules-runtime.js?hash=d3c3e5d67c95f97a60888bda7373292efad3be5e:56)
    at getOwn (modules-runtime.js?hash=d3c3e5d67c95f97a60888bda7373292efad3be5e:216)
    at fileAppendIdPart (modules-runtime.js?hash=d3c3e5d67c95f97a60888bda7373292efad3be5e:456)
    at modules-runtime.js?hash=d3c3e5d67c95f97a60888bda7373292efad3be5e:480
    at Array.every (<anonymous>)
    at fileAppendId (modules-runtime.js?hash=d3c3e5d67c95f97a60888bda7373292efad3be5e:478)
    at fileResolve (modules-runtime.js?hash=d3c3e5d67c95f97a60888bda7373292efad3be5e:503)
    at fileResolve (modules-runtime.js?hash=d3c3e5d67c95f97a60888bda7373292efad3be5e:562)
    at fileResolve (modules-runtime.js?hash=d3c3e5d67c95f97a60888bda7373292efad3be5e:562)

I haven’t even gotten to the point where I make my object observable yet.
I’ve looked at every issue in the system and they all have to do with issuing commands. I’m not even to that point yet! I also created bare bones projects for previous Meteor versions back to 1.7.0 and got the same issue every time. Am I missing something stupid? Sorry in advance and thanks for any help! Phil

[dnish]

Having exactly the same issue. Since the last MobX release, this error occurs. Reverting back to 5.7.0 solves the issue, so some changes in 5.8.0 cause the issue.

[mweststrate]

@clhaas this seems to be resolved in the next version of meteor, and can already be tried in the beta: https://github.com/meteor/meteor/issues/10409#issuecomment-453169097

(Honestly, I have no clue at this moment whether webpack 4 or meteor was in the wrong here, so the issue could be reopened if the problem happens outside meteor as well)