Hi Steve, that link shows up if the page someone is on is user submitted. You can disallow user submitted pages in individual page settings. Also, if you want to remove it from the sidebar completely, you can go to Websites > Theme _supporter_nav.html and remove that line:

{% if page_type == 'User Page' %}
<li class="on"><a href="{{ site.edit_pages_url }}">{{ "fugue-document-share" | icon }} Your pages</a></li>
{% else %}

Please note that you need to be using a custom theme before making changes. 

Thanks.