Javascript async keyword not recognized for a class method

Using Dreamweaver for coding php is really different from JavaScript where I had to turn off a lot of uneuseful "errors" warnings. I did it consulting the experts and documentation of ecmascript starndards.

But as I started to work with classes, this error is appearing and disturbing the code debug. DW points the error and won't check the rest:

    async cameraIni() {
        var inst = this;
        this.Camera.inibutton.disabled = true;
        this.Camera.stream = await navigator.mediaDevices.getUserMedia({ video: true, audio: false });
        this.Camera.video.srcObject = this.Camera.stream;
        console.log("imgUpload Camera straming...");
        this.Camera.video.play();
    }

ERROR: Parsing error: Unexpected token cameraIni

The code will work normally in browsers, also is widelly used by this kind of application with media.

I think we might consider this a real bug. Is there some workaround?