“edit post” link doesn’t appear in firefox

I’m using

<?php edit_post_link(); ?>

in my page template

<?php get_header(); ?>

<div id="page">
 <?php if (have_posts()) : while (have_posts()) : the_post(); ?>
  <h6><a href="<?php the_permalink() ?>" rel="bookmark"><?php the_title(); ?></a></h6>
<?php edit_post_link(); ?>
  <?php the_content(__('Read more'));?>
 <?php endwhile; else: ?>
  <p><strong>There has been a glitch in the Matrix.</strong><br />
  There is nothing to see here.</p>
  <p>Please try somewhere else.</p>
 <?php endif; ?>
</div><!-- end #page-->

<?php get_sidebar(); ?>
<?php get_footer(); ?>

and for some reason the “edit” like doesn;t appear in firefox. This is the first time I had problems with Firefox.. it appears in Chrome. I have no idea how to fix this.