Shortcodes break Twig processing in pages

\```
title: Test
process:
    markdown: true
    twig: true
\```

This is a test page.

{{ test }}

Here is another line.

[section name="test"]
This line is in a shortcode.
[/section]

<?php
namespace Grav\Theme;

use Grav\Common\Theme;

class Antimatter extends Theme
{
  public static function getSubscribedEvents()
  {
    return [
      'onTwigSiteVariables' => ['onTwigSiteVariables', 0]
    ];
  }

  public function onTwigSiteVariables()
  {
    $this->grav['twig']->twig_vars['test'] = 'Hello World!';
  }
}

{% extends 'partials/base.html.twig' %}

{% block content %}
    {{ page.content }}

    <h2>Extra Content</h2>

    <p>
        {{ shortcode.section.test }}
    </p>
{% endblock %}

    public static function getSubscribedEvents()
    {
        return [
            'onTwigPageVariables' => ['onTwigPageVariables', 0],
            'onTwigSiteVariables' => ['onTwigSiteVariables', 0]
        ];
    }

    public function onTwigPageVariables()
    {
        $this->grav['twig']->twig_vars['test'] = 'Hello World! in Page';
    }

    public function onTwigSiteVariables()
    {
        $this->grav['twig']->twig_vars['test'] = 'Hello World! in Site';
    } 
---