CloseButtonProperty

open class MyComponent : Component<Unit>, CloseButtonProperty by CloseButtonMixin(ComponentProperty{})  {
//                                        ^^^^^^^^^^^^^^^^^^^    ^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^^^
//                                        implement interface    delegate to      inject empty custom
//                                                               mixin            styling
     override fun render(/* params omitted */) {
          div {
              // check if closeButton is needed and render it then
              if (hasCloseButton.value) {
                  closeButtonRendering.value(this) handledBy closeHandler
                  //                               ^^^^^^^^^^^^^^^^^^^^^^
                  //                               use return value (event)
                  //                               to handle it by your closing mechanism
              }
          }
      }
 }