Preferences: Prevent opening more than one window

src/lib/app/mainmenu.cpp

@@ -118,8 +118,12 @@ void MainMenu::showAboutDialog()
 
 void MainMenu::showPreferences()
 {
-    Preferences* prefs = new Preferences(m_window, this);
-    prefs->show();
+    if (!m_preferences)
+        m_preferences = new Preferences(m_window, this);
+
+    m_preferences->show();
+    m_preferences->raise();
+    m_preferences->activateWindow();
 }
 
 void MainMenu::quitApplication()

src/lib/app/mainmenu.h

@@ -26,6 +26,7 @@
 
 class QMenuBar;
 
+class Preferences;
 class HistoryMenu;
 class BookmarksMenu;
 class BrowserWindow;
@@ -122,6 +123,7 @@ private:
 
     QHash<QString, QAction*> m_actions;
     QPointer<BrowserWindow> m_window;
+    QPointer<Preferences> m_preferences;
 
     QMenu* m_menuFile;
     QMenu* m_menuEdit;