My Kynetx app uses float_html() to put up a box full of content.

rule float_box {
  select when pageview ".*"
  pre {
    content = <<
      <div id='messagebox'>
      <h3>Floating Message Box</h3>
      <ul id='my_list'></ul>
      </div>
    >>;
  }
  float_html("absolute","top:25px","right:20px",content);
}

rule fill_box {
  select when pageview ".*"
  foreach ["alpha","bravo","charlie"] setting (list_item)
  append("#my_list", "<li>#{list_item}</li>");
}

The app (a421x27) is used from a bookmarklet. If you click the bookmarklet twice on the same page you get double content.

Is there any way to detect that the box is already on the screen and reuse it?