fix: do not redraw on read-only actions (#5682)

zellij-server/src/tab/mod.rs

@@ -2350,13 +2350,16 @@ impl Tab {
                 None
             };
         }
+        let was_dimmed = self.dimmed_clients.contains(&client_id);
         self.mode_info.borrow_mut().remove(&client_id);
         self.connected_clients.borrow_mut().remove(&client_id);
         self.mouse_help_text_visible.remove(&client_id);
         self.mouse_last_pane_id.remove(&client_id);
         self.last_mouse_activity_time.remove(&client_id);
-        self.set_client_dimmed(client_id, false);
-        self.set_force_render();
+        if is_connected_to_this_tab || was_dimmed {
+            self.set_client_dimmed(client_id, false);
+            self.set_force_render();
+        }
     }
     pub fn drain_connected_clients(
         &mut self,

zellij-server/src/tab/unit/tab_tests.rs

@@ -894,6 +894,62 @@ pub fn cannot_split_panes_horizontally_when_active_pane_is_too_small() {
     );
 }
 
+#[test]
+pub fn removing_a_client_not_connected_to_the_tab_does_not_force_render() {
+    let size = Size {
+        cols: 121,
+        rows: 20,
+    };
+    let stacked_resize = true;
+    let mut tab = create_new_tab(size, stacked_resize);
+    for pane in tab.tiled_panes.panes.values_mut() {
+        pane.set_should_render(false);
+    }
+    tab.remove_client(99);
+    assert!(
+        tab.tiled_panes.panes.values().all(|p| !p.should_render()),
+        "removing a client that never viewed this tab must not trigger a full re-render"
+    );
+}
+
+#[test]
+pub fn removing_a_client_not_connected_to_the_tab_clears_its_dimming() {
+    let size = Size {
+        cols: 121,
+        rows: 20,
+    };
+    let stacked_resize = true;
+    let mut tab = create_new_tab(size, stacked_resize);
+    tab.set_client_dimmed(99, true);
+    for pane in tab.tiled_panes.panes.values_mut() {
+        pane.set_should_render(false);
+    }
+    tab.remove_client(99);
+    assert!(!tab.dimmed_clients.contains(&99));
+    assert!(
+        tab.tiled_panes.panes.values().all(|p| p.should_render()),
+        "removing a dimmed client must re-render to clear the dimming"
+    );
+}
+
+#[test]
+pub fn removing_a_client_connected_to_the_tab_forces_render() {
+    let size = Size {
+        cols: 121,
+        rows: 20,
+    };
+    let stacked_resize = true;
+    let mut tab = create_new_tab(size, stacked_resize);
+    for pane in tab.tiled_panes.panes.values_mut() {
+        pane.set_should_render(false);
+    }
+    tab.remove_client(1);
+    assert!(
+        tab.tiled_panes.panes.values().all(|p| p.should_render()),
+        "removing a client that was viewing this tab must re-render it for the remaining clients"
+    );
+}
+
 #[test]
 pub fn split_in_direction_without_a_connected_client_still_creates_the_pane() {
     let size = Size {