I’m experiencing this bug as well.
See Image
When searching for example: Hematoxylin
Delafield’s <span class="search-everything-highlight-color" style="background-color:#f2f282">Hematoxylin</span>
OK i think i figured it out. Here’s the code:
<div id="navigation">
<ul>
<li<?php if(!get_adjacent_post(false, '', false)) { echo ' class="hide"'; } ?>><?php next_post_link('%link', 'Next »'); ?></li>
<li>Comment</li>
<li<?php if(!get_adjacent_post(false, '', true)) { echo ' class="hide"'; } ?>><?php previous_post_link('%link', '« Previous'); ?></li>
</ul>
</div>
I’ll just hide the li HTML tag with CSS