The issue stems from the preview being in an undefined style.

1. Go to configuration -> image styles and review the styles available. I have a style called "200x200 thumb".

2. After adding an image field to a content type, go to manage form display, expand the display of the image, and specify an existing style from step 1 as the preview style.

After taking these steps, the page for adding/editing this content type should render correctly.