Javascript: Why Is Our Website Extremely Slow In A Terminal Services Session?

We created a website that relies heavily on Javascript and has quite a lot of DOM-elements. In all browsers, even IE7 and IE8, this works fine. The user experience is a bit faster

Solution 1:

We finally found out the reason behind the delays !

We use Jquery UI with a theme that has many rounded corners (using CSS).

The rounded corners bring IE9 to a grinding halt in a Terminal Services session!! (IE10 doesn't seem to have this same problem).

Unfortunately there's no way to detect if someone is using Terminal Services, because Microsoft was stupid enough to use the same browser version number for Windows 7 and Windows 2008 Server (!), so we decided to disable rounded corners on our website for all users with IE9.