iMac desktop trouble!

[athinamj]

Hey I have a strange problem!
Yesterday as I was browsing in Firefox I minimized it for a while and noticed that on the desktop I could see some letters from the firefox theme. It was like they remained on the desktop even though firefox was minimizedI I have never confronted such an issue and frankly I don't know what to do. I contacted Mac service and they advised me to activate Screen Saver and let it on for hours so that it would clean up these remains from the desktop! I did so, I left it about 4 hours but the issue is still there. What can I do?

 

[spinnerlys]

Did a restart help? It might be a GPU driver issue, which can be resolved with a restart.

 

[athinamj]

Unfortunately I restarted but it didn't help!

 

[spinnerlys]

Unfortunately I restarted but it didn't help!

Can you post a screenshot?

Taking screenshots in Mac OS X.
How to Use Preview for Basic Image Editing: Crop, Rotate and Resize
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[athinamj]

This is a screenshot of my firefox window. Let me describe what I see as printed letters on the desktop!
As you look at the image I can see the letters on the left corner below and the letters on the right corner below, for example I can see the line "Michael Jackson-Forever the King of Pop etc and the letters from the firefox bar on the upper part of the window. The upper bar with the symbols of the browser is visible on the upper part of my desktop as it is on firefox!