Make Clipboard argument in Widget trait mutable

native/src/widget/scrollable.rs

@@ -162,9 +162,9 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
-        messages: &mut Vec<Message>,
         renderer: &Renderer,
-        clipboard: Option<&dyn Clipboard>,
+        clipboard: &mut dyn Clipboard,
+        messages: &mut Vec<Message>,
     ) -> event::Status {
         let bounds = layout.bounds();
         let is_mouse_over = bounds.contains(cursor_position);
@@ -205,9 +205,9 @@ where
                 event.clone(),
                 content,
                 cursor_position,
-                messages,
                 renderer,
                 clipboard,
+                messages,
             )
         };