When you start typing a question or and answer and then include an image through the editor button and uploading it from your computer then this might look like this in the editor/preview
Unfortunately, after finally publishing the post, the last sentence "And then simply go on writing, ..." and the image link is fused into one line which makes the final post look like this, where the image is not shown:
This was under the latest OS X 10.10 with Google Chrome Canary.
Dear Patrick, thank you for reporting this. What OS and browser are you using?