diff --git a/crates/fj-viewer/src/viewer.rs b/crates/fj-viewer/src/viewer.rs
index 95f423bbe..3f9ea1898 100644
--- a/crates/fj-viewer/src/viewer.rs
+++ b/crates/fj-viewer/src/viewer.rs
@@ -36,8 +36,8 @@ impl Viewer {
     }
 
     /// Access the cursor
-    pub fn cursor(&self) -> Option<NormalizedScreenPosition> {
-        self.cursor
+    pub fn cursor(&mut self) -> &mut Option<NormalizedScreenPosition> {
+        &mut self.cursor
     }
 
     /// Toggle the "draw model" setting
diff --git a/crates/fj-window/src/display.rs b/crates/fj-window/src/display.rs
index 3acfd7548..239fa85c2 100644
--- a/crates/fj-window/src/display.rs
+++ b/crates/fj-window/src/display.rs
@@ -32,7 +32,7 @@ pub fn display(model: Model, invert_zoom: bool) -> Result<(), Error> {
             &event,
             &window,
             &held_mouse_button,
-            &mut viewer.cursor(),
+            viewer.cursor(),
             invert_zoom,
         );
         if let Some(input_event) = input_event {