Why is my web app getting these errors in Firefox but not other browsers?

I asked this question on Stack Overflow and didn’t get any responses and I’m still completely lost on this so now I am trying to reach out here. I am completely lost as to what to do. Here is the link to my question: http://stackoverflow.com/questions/31713971/

The web app that I am building in meteor works in chrome and I.E.(Other than a UI bug in I.E.) but it starts acting strange in Firefox. When I run it on my localhost and on the deployment to meteor.com, I don’t get any errors in the console in the browsers’ developer tools.

When I run it in Firefox, things start acting weird. On Mac OSX, if I run the app on my localhost and open it in FF it is just fine. However, when I open up the app that deployed to meteor.com via meteor deploy [my-app-url].com, I get the following errors but I can still use everything in my app:

Error 1:
mutating the [[Prototype]] of an object will cause your code to run very slowly; instead create the object with the correct initial [[Prototype]] value using Object.create

Error 2:
Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource 
at https://ddp--3071-[my-app-url].com/sockjs/info?cb=v9pygo9mzn. (Reason: CORS request failed).

While right now I am not able to figure out what is causing the first error, I am mostly worried about the second error.

When I open up the app from it’s deployment in FF on Windows 8, I get the first error once, and then I get the second error repeatedly and the app never loads(it just stays on my loading template from the iron router). My deployed app runs just fine on Chrome and I.E.

I don’t send any kind of request to another server in my app, so I am not sure why I am getting a CORS request error. I have not set up SSL or began to make a certificate yet, so I am not sure if this could be causing this kind of error in FF as I got another exception on my login page in FF on my localhost saying that I shouldn’t have password elements when I’m not using https.

Does anyone know what could be causing this?

Sorry that I provide any code, as I don’t know what code I would post to solve this problem since I don’t actually request anything from another server in code that I have written.

Thanks in advance for any responses!

Same issue – I am using Meteor 1.2.0.2. with FireFox 41.0

mutating the [[Prototype]] of an object will cause your code to run very slowly; 
instead create the object with the correct initial [[Prototype]] value using Object.create

For me it was related to: this.next() in onBeforeAction().

Meteor.makeErrorType = function (name, constructor) {
    ....
    if () {
        // V8 environments (Chrome and Node.js)
        }
    else {
      // Firefox
      var e = new Error;
      e.__proto__ = errorClass.prototype;   <<<<<<<<<<< triggers the message.
    ....
    }

Only Firefox will get that message.
Found in “packages/meteor/errors.js”