diff --git a/app/src/handlers/itemhandler.h b/app/src/handlers/itemhandler.h
index 43d50683190b3038c4833204144c3dd43227cadc..83ebe3a187e3d6ea3be885142e95620ecc2e28dc 100644
--- a/app/src/handlers/itemhandler.h
+++ b/app/src/handlers/itemhandler.h
@@ -31,9 +31,9 @@ signals:
 public slots:
     QJsonObject metadataSet() const;
 
-    void getItem(const QString &command, const QString &url, const QString &installType, const QString &filename = "",
-                 const QString &providerKey = "", const QString &contentId = "");
-    void getItemByOcsUrl(const QString &ocsUrl, const QString &providerKey = "", const QString &contentId = "");
+    void getItem(const QString &command, const QString &url, const QString &installType, const QString &filename = QString(),
+                 const QString &providerKey = QString(), const QString &contentId = QString());
+    void getItemByOcsUrl(const QString &ocsUrl, const QString &providerKey = QString(), const QString &contentId = QString());
     void uninstall(const QString &itemKey);
 
 private slots:
diff --git a/app/src/handlers/ocsapihandler.h b/app/src/handlers/ocsapihandler.h
index 9e59f9ec51bf0d6924d76e5e6df773656cc313ff..c761f4b69704bb2bdd87fc1f592e7e22e7443b75 100644
--- a/app/src/handlers/ocsapihandler.h
+++ b/app/src/handlers/ocsapihandler.h
@@ -17,9 +17,9 @@ public slots:
     bool removeProvider(const QString &providerKey) const;
     bool updateAllCategories(bool force = false) const;
     bool updateCategories(const QString &providerKey, bool force = false) const;
-    QJsonObject getContents(const QString &providerKeys = "", const QString &categoryKeys = "",
-                            const QString &xdgTypes = "", const QString &packageTypes = "",
-                            const QString &search = "", const QString &sortmode = "new", int pagesize = 25, int page = 0) const;
+    QJsonObject getContents(const QString &providerKeys = QString(), const QString &categoryKeys = QString(),
+                            const QString &xdgTypes = QString(), const QString &packageTypes = QString(),
+                            const QString &search = QString(), const QString &sortmode = QString("new"), int pagesize = 25, int page = 0) const;
     QJsonObject getContent(const QString &providerKey, const QString &contentId) const;
 
 private:
diff --git a/app/src/websockets/websocketserver.h b/app/src/websockets/websocketserver.h
index 350903a064f95bd72cbf2d98118eb8cb9d611fa2..cfd2bcacb99a42610e5c12f363e680dbedf0f723 100644
--- a/app/src/websockets/websocketserver.h
+++ b/app/src/websockets/websocketserver.h
@@ -18,7 +18,7 @@ class WebSocketServer : public QObject
     Q_OBJECT
 
 public:
-    explicit WebSocketServer(ConfigHandler *configHandler, const QString &serverName = "WebSocketServer", quint16 serverPort = 0, QObject *parent = nullptr);
+    explicit WebSocketServer(ConfigHandler *configHandler, const QString &serverName = QString("WebSocketServer"), quint16 serverPort = 0, QObject *parent = nullptr);
     ~WebSocketServer();
 
 signals: