Druplicon is a Feature (Embedded Media Field Overlay Post)

A Drupal mask over thumbnails...
http://drupal.org/node/587562

"A strange bug with the last version, ie a span tag wich appears over thumbnails"

It's a slightly scary Druplicon.

AlexUA: "This is a feature, and you can disable it on the main Emfield configuration page."

By the way... the Problem this Update Fixed, and the Drupal Problem-solving Approach

Go to the page of the module that has the problem.

In the right-hand sidebar of the project page, type a keyword related to your problem.

http://drupal.org/project/emfield

Issues for Embedded Media Field
To avoid duplicates, please search before submitting a new issue. 'disappear'

http://drupal.org/project/issues/emfield?text=disappear&status=All

Custom Thumbnail Files Disappear After a Few Hours
http://drupal.org/node/605674

oh, wait, no, the first thing you do with a bug is make sure the module is at it's latest version.

Seriously? You've spent how long on this and haven't done any of this? When you are the first to take this problem, it is taken for granted that you have searched the module's issue queue.