Check destination pages for duplicate anchors

[ascott18]

It would be nice if this tool could check if the fragment target of a link has multiple matching elements on the destination page. This duplication on the destination is almost always undesirable and unintentional.

e.g.

/page1
<a href="/page2#target /></a>

/page2
<h1 id="target">Target 1</target>
<h1 id="target">Target 2</target>

would generate an error because of multiple id=target in the destination page.