#link outside of the #back-top block and empty paragraph at the end of page

With the new 2.0 module, this is the code generated:

<p id="back-top" style="display: block; ">
  <a href="#top">
    <span></span>
  </a>
</p>
<div id="link">
  <a href="#top">Back To Top</a>
</div>
<p></p>

Strange thing is also that div#link isn't inside the #back-top block, as the js suggests. As a consequence, if I choose the label to be displayed, it doesn't inherit the #back-top style. E.g., if I set the button to be on the right side, the label stays on the left, unstyled.

Anyway, the label being displayed or not, there's an empty line at the end of the page, that breaks the layout: my pages have a dark stripe at the very bottom of the page, but with the module enabled the dark stripe is followed by another white stripe, pretty impossible to deal with.

Good news is that I found that replacing a block item (div) with an inline one (span), solves the issue. Please see the attached patch, it works for me.