If you have an errormessage like 'duplicate key’then this is presented as a modal form.
But this small form is centered in the iframe it is shown.
If this iframe is large then you will miss the errormessage because it is virtual out of the screen.
I would prefer to be able to have a configurable errormessage line or the possibility to align te
message on a fixed position.
Same goes for modal forms.
If you have more iframes beneath each other and you request a modal form then this will be shown with
the iframe as parent.
Thus can be partly out of the screen and you need to scroll. Would be great if this could be configured.
This post was written by Aducom, I have also this problem too.
I had a feeling that I had seen this before 
But yes, it is still a problem.