A member of my team recently created a new revision that included some new PNGs. Whenever I select "Show Raw File (Right)" from the view options for these images, however, I'm shown a blank page (in both Safari and Chrome).
I looked at the `phabricator_file.files` table, and it appears that these image files have a `mimeType` of `text/plain` instead of `image/png`, which may be related.