__rearrangeInvokersAndContent() {
    const invokers = /** @type {HTMLElement[]} */ (
      Array.from(this.children).filter(child => child.slot === 'invoker')
    );

    const contents = /** @type {HTMLElement[]} */ (
      Array.from(this.children).filter(child => child.slot === 'content')
    );

    const accordion = this.shadowRoot?.querySelector('slot[name=_accordion]');

    if (accordion) {
      invokers.forEach((invoker, index) => {
        invoker.classList.add('invoker');
        // eslint-disable-next-line no-param-reassign
        invoker.slot = '_accordion';

        contents[index].classList.add('content');
        contents[index].slot = '_accordion';
      });
    }
  }
@private

 Moves all invokers and content to slot[name=_accordion] in correct order so focus works
 correctly when the user tabs.