diff --git a/cockatrice/src/settings/settings_manager.cpp b/cockatrice/src/settings/settings_manager.cpp
index fc4733880..dc2da741e 100644
--- a/cockatrice/src/settings/settings_manager.cpp
+++ b/cockatrice/src/settings/settings_manager.cpp
@@ -5,7 +5,10 @@ SettingsManager::SettingsManager(const QString &settingPath, QObject *parent)
 {
 }
 
-void SettingsManager::setValue(QVariant value, QString name, QString group, QString subGroup)
+void SettingsManager::setValue(const QVariant &value,
+                               const QString &name,
+                               const QString &group,
+                               const QString &subGroup)
 {
     if (!group.isEmpty()) {
         settings.beginGroup(group);
@@ -26,7 +29,7 @@ void SettingsManager::setValue(QVariant value, QString name, QString group, QStr
     }
 }
 
-void SettingsManager::deleteValue(QString name, QString group, QString subGroup)
+void SettingsManager::deleteValue(const QString &name, const QString &group, const QString &subGroup)
 {
     if (!group.isEmpty()) {
         settings.beginGroup(group);
@@ -47,7 +50,7 @@ void SettingsManager::deleteValue(QString name, QString group, QString subGroup)
     }
 }
 
-QVariant SettingsManager::getValue(QString name, QString group, QString subGroup)
+QVariant SettingsManager::getValue(const QString &name, const QString &group, const QString &subGroup)
 {
     if (!group.isEmpty()) {
         settings.beginGroup(group);
diff --git a/cockatrice/src/settings/settings_manager.h b/cockatrice/src/settings/settings_manager.h
index d9543612e..0a4757e58 100644
--- a/cockatrice/src/settings/settings_manager.h
+++ b/cockatrice/src/settings/settings_manager.h
@@ -11,7 +11,7 @@ class SettingsManager : public QObject
     Q_OBJECT
 public:
     explicit SettingsManager(const QString &settingPath, QObject *parent = nullptr);
-    QVariant getValue(QString name, QString group = "", QString subGroup = "");
+    QVariant getValue(const QString &name, const QString &group = "", const QString &subGroup = "");
     void sync();
 
 signals:
@@ -20,8 +20,8 @@ public slots:
 
 protected:
     QSettings settings;
-    void setValue(QVariant value, QString name, QString group = "", QString subGroup = "");
-    void deleteValue(QString name, QString group = "", QString subGroup = "");
+    void setValue(const QVariant &value, const QString &name, const QString &group = "", const QString &subGroup = "");
+    void deleteValue(const QString &name, const QString &group = "", const QString &subGroup = "");
 };
 
 #endif // SETTINGSMANAGER_H