Issues with the correct displaying of the Dashboard interface may be due to different causes. The first thing to check is the zoom level of your browser: normally, this may be visible to the right of the URL bar, or through the "View" section of your browser. We had some reports of browsers not displaying the main tab correctly for zoom levels under 100%. Most browsers allow you to reset the zoom level to 100% by clicking Control (or Command) and 0 (zero).
If the zoom level fix didn't work, make sure you are using an up to date browser and try opening the Dashboard with another browser. 
If the issue persists, report the bug directly from the Dashboard, attach some screenshots and let us know that you have already tried everything suggested here.