XF 2.2 Collapsing/expanding sidebar widgets

[valdet]

I didn't post this in Suggestions forum, because as it is a common (obvious) feature in websites, it may have been suggested before, but this is a fairly simple suggestion for which I think it would help with forums that could have too many sidebar widgets.

It would be really helpful to be able to have the widgets collapse (or expand), similar to how categories work.



A quick sample which also saves the state of the widget between session/pageviews, whether it is collapsed or not

HTML:

<div class="widget">
  <p align="right" class="expand"><a href="#">🔽</a></p>
  <p class="content">This is the Xenforo widget content</p>
</div>

Javascript:

// Check if there's a saved state in localStorage and apply it
$(document).ready(function() {
  $('.content').each(function() {
    var $this = $(this);
    var isOpen = localStorage.getItem('content_' + $this.index());
    if (isOpen === 'true') {
      $this.show();
      $this.closest('.widget').find('.expand a').text('🔼');
      $this.closest('.widget').find('.expand img').hide();
    } else {
      $this.hide();
    }
  });
});

$('.expand').click(function() {
  var $expandButton = $(this).find('a'); // Select the anchor tag inside .expand-one
  var $content = $(this).closest('.widget').find('.content');
  $content.slideToggle('slow', function() {
    var $this = $(this);
    if ($this.is(':visible')) {
      $expandButton.text('🔼');
      $expandButton.find('img').hide();
      localStorage.setItem('content_' + $this.index(), true);
    } else {
      $expandButton.text('🔽');
      $expandButton.find('img').show();
      localStorage.setItem('content_' + $this.index(), false);
    }
  });
});

Preview:

Expand and collapse widgets, with button state saved in localstorage - JSFiddle - Code Playground

Test your JavaScript, CSS, HTML or CoffeeScript online with JSFiddle code editor.

jsfiddle.net

It is fairly straightforward in HTML, but the question is how to do this in Xenforo?
I couldn't find the default widget wrapper, where I would "hack" this code into, so I hope there's a quick way to do this.

Thanks.