A node with just an img tag and nothing else does not display

If you create a node with just an image tag and nothing else, it gets removed by the filter module on display. If you add text before or after the tag it displays properly.

To replicate:

1. Add to the list of allowed tags in the filtered html input type
2. Create a node with just an img tag and nothing else

Expected result: It should display the image
Actual result: it displays nothing