Focusing the dynamic properties dialog causes annoying scroll to top behaviour

Steps to reproduce

Bluring and then focusing the DynamicProperties dialog causes it to scroll to top.

Steps to reproduce:

1. In Admin, add enough dynamic properties to cause the dialog to scroll. Two xhtml-properties should do the trick

2. In Edit, open the dynamic properties dialog

3. Scroll to the bottom of the dialog content

4. Click outside the dialog and then inside the dialog

Observe:

the dialog content is scrolled to the top