XSLT xml-stylesheet not embedding in Codemirror on preview screen

Can somebody try to help with this problem.

The XSL file does not load properly while being embedded by main XML file. The platforms are Codemirror and Codeparser, while the framework is Laravel 5. I know that the code is inserted in SQL, as well as pulled out properly but it seems that Codemirror comments out the <?xml tags.

Here is the code and Mozilla Inspector pic:

1. XML code

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="http://www.website.com/dir/dir/person.xsl"?>
<root>
    <person>
    <fname>Allan</fname>
    <lname>Poe</lname>
    <year>1832</year>
    </person>    
    ...
</root>

2. XSL code

<?xml version="1.0"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
    <xsl:output method="html"/>
     <xsl:template match="/">
        <html>
            <head>
                <title>person.xsl</title>
            </head>
            <body>
                <h2 style="color:green;">persons</h2>
                <table border="1">
                    <tr style="color:#9acd32">
                        <th>name</th>
                       ...
                    <xsl:for-each select="/root/fname">
                    <xsl:sort select="fname" />
                        <xsl:if test="name!='...'">
                      ...
                      ...      
                      ...          
        </html>
    </xsl:template>
</xsl:stylesheet>

3. Results

Allan Poe 1932 …

As you can see, there is no styling in the results. the only conclusion so far that I’ve got is that Codemirror or Codeparser filtered out the XML mode (although selected). Mozilla Inspector shows XML tags commented out:

4. Mozilla Inspector

<div class="CodeMirror" ...>
   <iframe id="codeparser-preview-..." ...>
      #document
         <!--?xml version="1.0" encoding="UTF-8"?-->
         <!--?xml-stylesheet type="text/xsl" href="http://www.website.com/dir/dir/person.xsl"?-->
         <html>...</html>
     ...

Cannot figure where to change this behaviour ( or elsewhere)