the html is a bit in a mess at the end of your single post:
<div id="footer" role="contentinfo">
<p>
<!-- 30 queries. 4.968 seconds. -->
</p>
</div>
</div>
<script type='text/javascript' src='https://crozon.ca/wordpress/wp-content/plugins/contact-form-7/jquery.form.js?ver=2.47'></script>
<script type='text/javascript' src='https://crozon.ca/wordpress/wp-content/plugins/contact-form-7/scripts.js?ver=2.4.1'></script>
</body>
</html></div>
</div>
<div class="postfooter"></div>
your <div class="postfooter"></div>
should be somewhere further up in the code, not after the closing body and html tags.
see also https://validator.w3.org/check?uri=http%3A%2F%2Fwww.crozon.ca%2Fblog%2Ftest-post&charset=%28detect+automatically%29&doctype=Inline&group=0
this bit at the end of single.php:
<?php get_sidebar(); ?>
<?php get_footer(); ?>
</div>
</div>
<div class="postfooter"></div>
might need resorting –
probably remove all code after the ‘get_footer’ line;
and re-insert the <div class="postfooter"></div>
into comments.php(?) after the
</div><!-- #comments -->
if you have problems sorting this, you could paste the code of comments.php into a https://wordpress.pastebin.com/ and post the link to it here.