fix floating panels and iOS export picking

src/node_panel_floating.cpp

@@ -29,6 +29,7 @@ void NodePanelFloating::init_controls()
     m_flood_events = true;
     m_capture_children = true;
     m_container = find("container");
+    m_title = find<NodeText>("title");
     m_button_minimize = find<NodeButton>("button-minimize");
     m_button_minimize->on_click = [this](Node*) {
         m_container->ToggleVisibility();