In improving the alt-texts on Mi Yodeya, I came across this odd bug while editing a question.
The picture in the post shows normally, when I'm not editing it:
However, when editing the post, the picture disappears from the preview:
Removing the mouseover text didn't change anything. I also tried editing the post in incognito mode, to check if the issue had to do with inline editing; the same issue appeared there.
I'm using Chrome on Windows 8. This issue hasn't (as far as I could tell) occurred for any other posts I've edited recently.