Recently I have begun experimenting with Lookit, a screen capture upload application. At this point I have not tried the upload capabilities. That is, my various screen captures are simply being saved locally.
When the screen capture is saved, a PNG is being created and, when viewed from Nautilus, an accurate thumbnail is displayed. However, when I attempt to view the file in an application such as the Image Viewer in Ubuntu, nothing is displayed. Additionally, when I tried to upload the file, photobucket.com choked. The Shotwell Photo Viewer also would not display the PNG. I did find that GIMP would display the image and could subsequently be edited.
What is the difference between the PNG produced by Lookit and PNGs produced by other applications? Is there a fix that allows the Lookit PNG to be viewed by all standard viewers?