core-bundle/src/Resources/contao/forms/FormHtml.php
public function parse($arrAttributes=null)
	{
		if (TL_MODE == 'BE')
		{
			$this->html = htmlspecialchars($this->html);
		}

		return parent::parse($arrAttributes);
	}
public function parse($arrAttributes=null)
	{
		if (TL_MODE == 'BE')
		{
			$this->html = htmlspecialchars($this->html);
		}

		return parent::parse($arrAttributes);
	}
Parse the template file and return it as string

@param array $arrAttributes An optional attributes array

@return string The template markup