Form editor is broken in Internet Explorer 8

[Tobias Lindqvist]

The following parts of the Form editor doesn't work in Internet Explorer 8:

Text input and Text box vanish from the left side list of elements when being placed into the form. They reappear when other elements are placed into the form.
Most elements don't have all options to change various attributes of the element. E.g. The header element can be re-sized but the user can't change the text of it.

Previewing (both internal and external) and Saving the form get broken due to errors. Loading, however, works fine.