old_contents: import Component from '@glimmer/component';
  import { action } from '@ember/object';
  
  export default class FormButtonComponent extends Component {
    isActing = false;
    @action
    handleClick() {
      if (!this.isActing && this.args.onClick) {
        const ret = this.args.onClick();
  
        if (ret.finally) {
          this.isActing = true;
          ret.finally(() => (this.isActing = false));
        }
        return ret;
      }
    }
  }
  
new_contents: import Component from '@glimmer/component';
  import { action } from '@ember/object';
  import { tracked } from '@glimmer/tracking';
  
  export default class FormButtonComponent extends Component {
    @tracked
    isActing = false;
    @action
    handleClick() {
      if (!this.isActing && this.args.onClick) {
        const ret = this.args.onClick();
  
        if (ret.finally) {
          this.isActing = true;
          ret.finally(() => (this.isActing = false));
        }
        return ret;
      }
    }
  }
  
subject: Make isActing tracked