I have a gridview with a button on each row, when I press the button it does a postback that builds the form to appear on a modalpopupextender, each row's form can be very different, so I can't build it beforehand. After building the controls on the MPE form, I do a MPE_form.Show(). It works fine but, it shows the popup below the grid before centring it on screen and being ready for input. The delay on one of the more complex forms can be 3-4 seconds.
This was using IE11. I tried it on chrome, and it does still very briefly display the popup below the grid, but it is a hell of a lot faster to display the form.
Is there anything I can do to make the popup not display until it's actually in a complete state ready for input ?