diff -ruN a/flameshot.pro b/flameshot.pro
--- a/flameshot.pro	2020-05-25 21:16:54.044214597 +0300
+++ b/flameshot.pro	2020-05-25 21:25:03.808676488 +0300
@@ -18,7 +18,7 @@
     QT  += dbus
 }
 
-CONFIG += c++11 link_pkgconfig
+CONFIG += c++11 link_pkgconfig qtsingleapplication
 
 #CONFIG += packaging   # Enables "make install" for packaging paths
 
@@ -63,7 +63,6 @@
 
 DEFINES += QT_DEPRECATED_WARNINGS
 
-include(src/third-party/singleapplication/singleapplication.pri)
 include(src/third-party/Qt-Color-Widgets//color_widgets.pri)
 
 DEFINES += QAPPLICATION_CLASS=QApplication
diff -ruN a/src/main.cpp b/src/main.cpp
--- a/src/main.cpp	2020-05-25 21:16:54.055215952 +0300
+++ b/src/main.cpp	2020-05-25 21:25:35.095744395 +0300
@@ -16,13 +16,13 @@
 //     along with Flameshot.  If not, see <http://www.gnu.org/licenses/>.
 
 #include "src/core/controller.h"
-#include "singleapplication.h"
 #include "src/utils/filenamehandler.h"
 #include "src/utils/confighandler.h"
 #include "src/cli/commandlineparser.h"
 #include "src/utils/systemnotification.h"
 #include "src/utils/pathinfo.h"
 #include "src/core/capturerequest.h"
+#include <QtSingleApplication>
 #include <QApplication>
 #include <QTranslator>
 #include <QTextStream>
@@ -44,7 +44,7 @@
 
     // no arguments, just launch Flameshot
     if (argc == 1) {
-        SingleApplication app(argc, argv);
+        QtSingleApplication app(argc, argv);
 
         QTranslator translator;
         QStringList trPaths = PathInfo::translationsPaths();