diff --git a/crates/ui-egui/src/backstage_tests.rs b/crates/ui-egui/src/backstage_tests.rs
index 9b3906a2..18be4599 100644
--- a/crates/ui-egui/src/backstage_tests.rs
+++ b/crates/ui-egui/src/backstage_tests.rs
@@ -535,3 +535,20 @@ fn print_slides_follow_the_settings() {
     bs.print_layout = "slides";
     assert_eq!(print_page_size(&bs, &doc), (doc.slide_size.width as f32, doc.slide_size.height as f32), "slides print slide-shaped");
 }
+
+/// Options in the File tab opens the Preferences dialog, and Cancel closes it (#782, #752).
+#[test]
+fn options_in_backstage_opens_preferences_and_cancel_closes_it() {
+    let mut h = harness(new_app());
+    h.get_by_label("File").click();
+    h.run_steps(3);
+    assert!(h.state().backstage_open());
+    h.get_by_label("Options").click();
+    h.run_steps(3);
+    assert!(h.state().dialog.is_some(), "Options opens Preferences dialog");
+    assert_eq!(h.state().dialog.as_ref().map(|d| d.id.as_str()), Some("preferences"));
+    h.query_all_by_role_and_label(Role::Button, "Cancel").next().expect("Cancel button").click_accesskit();
+    h.run_steps(3);
+    assert!(h.state().dialog.is_none(), "Cancel closes Preferences dialog");
+    assert!(h.state().backstage_open(), "Backstage remains open");
+}
diff --git a/crates/ui-egui/src/dialogs.rs b/crates/ui-egui/src/dialogs.rs
index 576a2297..9d2dbe08 100644
--- a/crates/ui-egui/src/dialogs.rs
+++ b/crates/ui-egui/src/dialogs.rs
@@ -2085,8 +2085,8 @@ fn body(app: &mut SlideApp, ui: &mut Ui, d: &mut Dialog) -> bool {
                 }
                 _ => about(app, ui),
             }
-            let (ok, _) = buttons(ui, "Close");
-            ok
+            let (ok, cancel) = buttons(ui, "Close");
+            ok || cancel
         }
         "autocorrect" => {
             let pr = &mut app.session.prefs;
diff --git a/crates/ui-egui/src/lib.rs b/crates/ui-egui/src/lib.rs
index 88674070..d449874e 100644
--- a/crates/ui-egui/src/lib.rs
+++ b/crates/ui-egui/src/lib.rs
@@ -2642,6 +2642,41 @@ mod tests {
         assert_ne!(s.session.prefs.snap_to_grid, before.snap_to_grid, "Done keeps snap to grid");
     }
 
+    /// About dialog: Close and Cancel each close the dialog.
+    #[test]
+    fn about_dialog_close_and_cancel_close_it() {
+        use egui_kittest::kittest::Queryable;
+        let mut harness = egui_kittest::Harness::builder().with_size(egui::vec2(1200.0, 800.0)).build_ui_state(
+            |ui, app: &mut SlideApp| {
+                app.logic(ui.ctx());
+                app.ui(ui);
+            },
+            SlideApp::new(Session::with_new(), Services::default()),
+        );
+        harness.run_steps(2);
+        harness.state_mut().run("app.about", json!({})).unwrap();
+        harness.run_steps(2);
+        assert!(harness.state().dialog.is_some());
+        harness
+            .query_all_by_role_and_label(egui::accesskit::Role::Button, "Cancel")
+            .next()
+            .unwrap_or_else(|| panic!("no Cancel button in About dialog"))
+            .click_accesskit();
+        harness.run_steps(2);
+        assert!(harness.state().dialog.is_none(), "Cancel closes About dialog");
+
+        harness.state_mut().run("app.about", json!({})).unwrap();
+        harness.run_steps(2);
+        assert!(harness.state().dialog.is_some());
+        harness
+            .query_all_by_role_and_label(egui::accesskit::Role::Button, "Close")
+            .next()
+            .unwrap_or_else(|| panic!("no Close button in About dialog"))
+            .click_accesskit();
+        harness.run_steps(2);
+        assert!(harness.state().dialog.is_none(), "Close closes About dialog");
+    }
+
     fn canvas_harness() -> egui_kittest::Harness<'static, SlideApp> {
         let mut harness = egui_kittest::Harness::builder().with_size(egui::vec2(1200.0, 800.0)).build_ui_state(
             |ui, app: &mut SlideApp| {