You are trying to set "Companion" which is a final field!

[Splash34]

Environment
Provide version numbers for the following components (information can be retrieved by running tns info in your project folder or by inspecting the package.json of the project:

CLI: 8.2.14
Cross-platform modules:
"tns-core-modules": "~6.5.15"
"nativescript-feedback": "^1.5.0",

Describe the bug
Calling this.feedback.show({..} ) fails with Error: You are trying to set "Companion" which is a final field! Final fields can only be read.

Add plugin into a new {N} project. Import and execute:

var test = require("nativescript-kotlintest");
test.doTest();

feedback.service.js :

import { Injectable } from '@angular/core';
import { Feedback, FeedbackType } from 'nativescript-feedback';

@Injectable({
  providedIn: 'root'
})
export class FeedbackService {
  private feedback: Feedback;

  constructor() {
    this.feedback = new Feedback();
  }

  showSuccessMessage(message: string) {
    this.feedback.show({
      message: message,
      type: FeedbackType.Success
    });
  }
}

Component.ts:

    login() {
      this.processing = false;
      this.authService.login(this.user.email, this.user.password).subscribe(
      data => {
        this.feedbackService.showSuccessMessage("test message");
        this.routerExtensions.navigate(['/bills/tabs'], { clearHistory: true });
       },
      error => {
        console.log(error);
      }
    );
  }

Expected behavior
To not crash.

Additional context:
Issue occur if function gets invoked.

Full stacktrace:

JS: ERROR Error: Uncaught (in promise): Error: You are trying to set "Companion" which is a final field! Final fields can only be read.
JS: Error: You are trying to set "Companion" which is a final field! Final fields can only be read.
JS:     at file:///node_modules/nativescript-feedback/feedback.js:17:0
JS:     at new ZoneAwarePromise file:///node_modules/@nativescript/angular/zone-js/dist/zone-nativescript.js:902:0
JS:     at Feedback.show file:///node_modules/nativescript-feedback/feedback.js:15:0
JS:     at FeedbackService.module.exports.push../app/shared/services/feedback.service.ts.FeedbackService.showSuccessMessage file:///src/app/shared/services/feedback.service.ts:15:18
JS:     at SafeSubscriber._next file:///src/app/auth/auth.component.ts:50:29
JS:     at SafeSubscriber.push.../node_modules/rxjs/_esm5/internal/Subscriber.js.SafeSubscriber.__tryOrUnsub file:///node_modules/rxjs/_esm5/internal/Subscriber.js:192:0
JS:     at SafeSubscriber.push.../node_modules/r...

Further github issue, which does not solve the problem:
NativeScript/android#1178