RadSlider and IE8 meta tag

[Jordan]

We are using ASP.NET AJAX 2010 and have a page that has a RadGrid with fixed headers and a RadSlider that is being used to filter records in the grid.  It works great in IE9, firefox, chrome, safari.  But in IE8 and below it takes 30 seconds to render the page.  We have narrowed the problem down to the RadSlider, and even further we have narrowed it down to browser- mode/document-mode.  If we don't set a X-UA-Compatible meta tag, or if we use IE=8 or IE=edge, then the delay occurs.

If we use IE=7 it loads quickly, but when we use that the radgrid is screwed up because the header columns don't match the width of the body columns.

Do you have any recommendations on getting these to work together?

[Jordan]

I've noticed that the same issue occurs on your demo pages here:

http://demos.telerik.com/aspnet-ajax/slider/examples/serversideapi/defaultcs.aspx
http://demos.telerik.com/aspnet-ajax/slider/examples/clientsideapi/defaultcs.aspx

And the browser is locked until the slider is fully rendered.  On the demo pages, it takes about 20 seconds to load in IE 8.

[Slav]

Hi Jordan,

Please note that the RadSlider control is functioning properly under IE8 or under Internet Explorer browser in IE8 mode. There are known slowdown issues with Internet Explorer 8 and the behavior that you have encountered is a result of the default performance of the browser, over which we have no control.

If by any chance the described effect causes JavaScript errors and breaks the functionality of the RadSlider control, please prepare and send a simple, runnable page that demonstrates the problem so that we can inspect it and determine what is causing it.

Regards,
Slav
the Telerik team