The http://drupal.org/project/media module cannot display the thumbnails of txt and pdf files in my installation. I'm not expecting a thumbnail of the actual txt or pdf content of course but a generic placeholder.
Display as list:
Display as thumbnail:
- no missing file (404) requests are being tracked in firebug
- this also affects the media popup file chooser from within content editing
- changing the theme doesn't solve this problem
- inspecting the "empty thumbnail" with firebug doesn't show anything useful, the
<a />is empty.