Issue
When the user causes a complete postback all of the panels associated with ModalPopupExtenders flicker and become visible for a moment before the page disappears as the browser loads the next page. NOTE: This is occurring while exiting the page, not when the page loads and could not be replicated on other pages.
What did not work
A quick Google search yielded this post relating to the flicker occassionaly seen when the page loads: http://mattberseth.com/blog/2007/08/how_to_stop_the_modalpopup_fli.html
To get around this, I explicitly set the display style to ‘none’ on the popup Panel. This has solved the problem.
I tried this two ways (not at the same time):
- I added display:none; to my css class that each panel uses.
- I added style=”display:none;” the to the panel’s tag (more…)