Does the BUI Extensibility Framework support ES6 classes?

Summary:

Are ES6 classes supported by BUI Extensibility Framework?

Content (required):

Hello,

Since 2017 our customer uses a CTI integration, that is a version based on the Twilio accelerator that integrates with Avaya.

We are now extending it functionality to allow to integrate with Avaya POM.

The thing is that we begin to get some errors in browser's console like follows:

Uncaught TypeError: Cannot read property 'someProp' of undefined.

When review the code reference, "someProp" is a property definded at class ctiTelephonyAddin with this.someProp = "someValue";

Trying to figure out whats going on with that error, found the following post regarding to: