contextComponent

components.button\.js

import Component from '@glimmer/component';

export default class extends Component {
  context = {
   	a: 1,
    b:2 
  };
}

components.coach\.js

import Component from '@glimmer/component';
import { action } from '@ember/object';

export default class extends Component {
  @action
  click(context) {
    console.log('Hello World');
    console.log('Context: ', context);
  }
}

controllers.application\.js

import Controller from '@ember/controller';

export default class ApplicationController extends Controller {
  appName = 'Ember Twiddle';
}

templates.application\.hbs

<Button />

templates.components.button\.hbs

<Coach as |coach|>
	<button {{on "click" (fn coach.onClick this.context)}}>This a button</button>
</Coach>

templates.components.coach\.hbs

{{yield (hash onClick=this.click)}}

twiddle\.json

{
  "version": "0.17.1",
  "EmberENV": {
    "FEATURES": {},
    "_TEMPLATE_ONLY_GLIMMER_COMPONENTS": false,
    "_APPLICATION_TEMPLATE_WRAPPER": true,
    "_JQUERY_INTEGRATION": true
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.5.1/jquery.js",
    "ember": "3.18.1",
    "ember-template-compiler": "3.18.1",
    "ember-testing": "3.18.1"
  },
  "addons": {
    "@glimmer/component": "1.0.0"
  }
}