testMouseNavigation() {
    simulateAllKeyEventsOnInput(KeyCodes.DOWN);

    /**
     * @suppress {strictMissingProperties} suppression added to enable type
     * checking
     */
    input.value = 'c, a';
    selection.setCursorPosition(input, 'c, a'.length);
    simulateAllKeyEventsOnInput(KeyCodes.A);
    mockClock.tick(500);

    const secondOption = asserts.assertElement(findNodeByInnerText(data[1]));
    const parent = secondOption.parentNode;
    assertFalse(classlist.contains(secondOption, 'ac-active'));

    const mouseOver = new GoogEvent(EventType.MOUSEOVER, secondOption);
    simulateEvent(new BrowserEvent(mouseOver, parent));
    assert(classlist.contains(secondOption, 'ac-active'));

    const mouseDown = new GoogEvent(EventType.MOUSEDOWN, secondOption);
    simulateEvent(new BrowserEvent(mouseDown, parent));
    const mouseClick = new GoogEvent(EventType.CLICK, secondOption);
    simulateEvent(new BrowserEvent(mouseClick, parent));

    assertEquals('c, aab, ', input.value);
  }
Ensure that mouse navigation with multiple inputs works.
     @suppress {checkTypes,strictMissingProperties} suppression added to enable
     type checking