Currently the click event is not triggered when RadButton is focused and enter key is pressed. This behavior is observed in FireFox and WebKit browsers only.

When the RadButton, validation controls and controls which are to be validated are set with the same ValidationGroup, the validation is performed despite setting RadButton's CausesValidation property to false.

Currently it is not possible to focus RadButton through tabbing navigation unless the TabIndex property is set. For the time being TabIndex of 0 can be set, so that the tab order on the page layout is not distracted. For example:

    <script type="text/javascript">
        function pageLoad() {
            //Getting the button's wrapper
            button1 = $find("<%=RadButton1.ClientID %>");
            buttonWrapper = $telerik.$(button1.get_element());

            //Set tabindex attribute to the span element
            buttonWrapper.attr("tabindex", "0");      
        }                 
    </script>

Note that TabIndex=0 is set to the span wrapper element of the RadButton's input with JavaScript as setting RadButton's TabIndex property to 0 will not take effect.

When there is a RadButton with configured ValidationGroup, the client-side ASP.NET validation on the page will not be executed, if there are validation controls, which use the same ValidationGroup. The unexpected behaviour is observed in FireFox and Opera.

When a RadButton with configured ValidationGroup is used on a master page its server-side event 'Click' is not raised in:
-Internet Explorer and Chrome, but FireFox and Opera.
-In all browsers when the master page contains a RadAjaxManager.