When I right click on an image shown in my browser to save it, it sometimes saves it with an HTM file extension. Once I rename the file to end in JPG, I can view the picture all right. If I save a dozen pictures, however, I will have to rename all the file extensions.

Pictures originally saved as HTM files and then renamed do not have a preview thumbnail embedded in them.

This can also happen when I am viewing only a picture in the browser (no other content) and I save the picture using FILE and SAVE from the menu bar.

So, why does it happen and how can I stop it happening? This is an intermittent problem.

Browser: Firefox 3.6.3
OS: Windows Vista
Chase Jones, your answer is moronic.