Reading is not your strong skill - I asked you to NAME what functionality in ASP.NET is only compatible with IE.
When authoring with the WebControls in ASP.NET Web Forms, the client browser is detected. If the client browser is Internet Explorer 5.5 or later, then a DHTML behavior behavior is included in the Web page. This content is downloaded automatically when authoring with WebControls in Web Forms, but it is also possible to use behaviors independently of the server-side authoring environment.
The WebControls deliver premium content and functionality to uplevel browsers and make extensive use of advanced client browser features. Most of the superior performance in the rendering and functionality in the uplevel browsers comes from the use of DHTML behaviors, which have their own Object Model.
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