F3 Escaping Problem

index.php

<?php

$root = dirname(__DIR__) . '/';

/** @var $fw \Base */
$fw = require $root . 'vendor/bcosca/fatfree/lib/base.php';

$fw->set('CACHE', 'folder=' . __DIR__ . '/tmp/cache/');
$fw->set('CASELESS', false);
$fw->set('DEBUG', 2);
$fw->set('TEMP', __DIR__ . '/tmp/');
$fw->set('UI', __DIR__ . '/');

$fw->set('value', '<p><span style="color:red;">R</span><span style="color:green;">G</span><span style="color:blue;">B</span> when not escaped</p>');

// Escapes `value` and stores the result as `value_escaped`.
$value_escaped = Template::instance()->render('value.html');
$fw->set('value_escaped', $value_escaped);

// Prints `value_escaped` as RAW text.
// Expected: escaped `value`.
// Result:   non-escaped `value`.
$value_result = Template::instance()->render('master.html');

echo '<h1>Expected (escaped `value`)</h1>';
echo $value_escaped;

echo '<h1>Result (non-escaped `value` instead of escaped `value_escaped`)</h1>';
echo $value_result;

master.html

{{ @value_escaped | raw }}

result.html

<h1>Expected (escaped `value`)</h1>&lt;p&gt;&lt;span style=&quot;color:red;&quot;&gt;R&lt;/span&gt;&lt;span style=&quot;color:green;&quot;&gt;G&lt;/span&gt;&lt;span style=&quot;color:blue;&quot;&gt;B&lt;/span&gt; when not escaped&lt;/p&gt;<h1>Result (non-escaped `value` instead of escaped `value_escaped`)</h1><p><span style="color:red;">R</span><span style="color:green;">G</span><span style="color:blue;">B</span> when not escaped</p>

value.html

{{ @value }}