You see on w3c.org messages like this:
"Line 1280, Column 389: ID "link-14" already defined …/www.wetteronline.de/deutsch.htm" id="link-14" class="track_this_link " title…
An "id" is a unique identifier. Each time this attribute is used in a document it must have a different value. If you are using this attribute as a hook for style sheets it may be more appropriate to use classes (which group elements) than id (which are used to identify exactly one element)."
change code near line 4400 from:
$imageoutput .= '" id="link-' . $linkitem['proper_link_id'] . '" class="track_this_link' . ( $linkitem['link_featured'] ? 'featured' : '' ). '" ' . $rel . $title . $target. '>';
to:
$imageoutput .= '" id="ilink-' . $linkitem['proper_link_id'] . '" class="track_this_link' . ( $linkitem['link_featured'] ? 'featured' : '' ). '" ' . $rel . $title . $target. '>';
