<script>
    (function () {
        try {
            var original_initialize = Telerik.Web.UI.RadMultiSelect.prototype._initialize;
            Telerik.Web.UI.RadMultiSelect.prototype._initialize = function () {
                var $selectElement = $(this.get_element());
                var $tempWrapper = $('<div></div>').insertBefore($selectElement);

                $selectElement.children().appendTo($tempWrapper);

                original_initialize.call(this);

                $tempWrapper.children().appendTo($selectElement.closest('.RadMultiSelect'));
                $tempWrapper.remove();
            }
        } catch (e) {
            // Nothing to do
        }
    })()
</script>

        <telerik:RadMultiSelect ID="rcbUsers" runat="server" Width="500px" DropDownHeight="200px"
            DataValueField="UserID" DataTextField="UserName" TagMode="Multiple" AutoPostBack="true">
            <ClientEvents OnLoad="onMultiSelectLoad" />
        </telerik:RadMultiSelect>
        <script>
        function onMultiSelectLoad(sender) {
            handleClientStateInput(sender);
        }
        function handleClientStateInput(sender) {
            // Chrome 131 breaking change fix
            var clientStateFieldId = sender.get_clientStateFieldID();
            var controlWrapper = sender.get_element();
            var parentContainer = controlWrapper.parentElement;

            if (!parentContainer) {
                return; // Exit if the parent container is not found
            }

            // Check if the ClientState input exists
            var existingInput = document.getElementById(clientStateFieldId);

            if (existingInput) {
                // Ensure the input is within the correct container
                if (existingInput.parentElement !== parentContainer) {
                    parentContainer.appendChild(existingInput);
                }
            } else {
                // Recreate the hidden input element if it doesn't exist
                var clientStateInput = document.createElement("input");
                clientStateInput.id = clientStateFieldId;
                clientStateInput.name = clientStateFieldId;
                clientStateInput.type = "hidden";
                clientStateInput.autocomplete = "off";

                // Set the initial value for the ClientState
                clientStateInput.value = sender.saveClientState();

                // Append the hidden input to the parent container
                parentContainer.appendChild(clientStateInput);
            }
        }
        </script>