I am experiencing a strange problem in WP 3.8
I am managing several WP installations, and this problem only shows up in some of them.
If I disable widgets in the admin dashboard, so there is only one column back, some of the 3.8 installations still shows the empty container with a dotted line.
This problem is independent of which browser is used, it's the same on chrome, firefox and IE.
This problem is independent of host, it randomly shows on different hosts.
In practical use, it is not a problem, only visually.
Se screendump: https://www.dropbox.com/s/zn9qvja7b6ilzi7/wp-admin-dotted.jpg
Any idea what is happening?