Maybe there is a setting on Facebook you could adjust to make it easier to view.
This is a bit of a mystery but I doubt very much if it is anything to do with McAfee. More likely this is a Windows appearance setting or your graphics card settings need adjusting.
Have you tried asking for help from whatever application that is you are using in that picture?
Or post on an independent Windows help group. I can steer you to some if you tell me what operating system this is.
It's not just the facebook application, I haven't went out looking but the two main sites it's on for me is Dailymotion and that facebook application.
I am using Windows Vista.
Also, just as a precaution. Download, install, update (very important) then run the FREE version of this software: http://www.malwarebytes.org/mbam.php
Let it remove anything it finds and reboot immediately when/if asked.