On my self hosted mediawiki I upload some documents (like ODT, DOC, XLS, ecc) and add one or more categories on it.
When I go on the category special page (eg Category:coverLetters) on the bottom I see the all documents related, BUT with a withe page thumbnail.
If I click on the thumb, Multimediawiki say "Oh sorry, the file cannot be viewed.[...] File does not exist: File:Fileicon.png".
I belive that MMV has to check if a file ends with .jpg, or png or image related extensions, and not to work with others.
Is it possibile to do?