fix unexpected close when launch external app (#2617)

* fix unexpected close when launch external app

* update

src/core/flameshot.cpp

@@ -411,6 +411,12 @@ void Flameshot::exportCapture(QPixmap capture,
     if (!(tasks & CR::UPLOAD)) {
         emit captureTaken(capture);
     }
+    // hacks: close a window to trigger qt's quitOnLastWindowClose
+    // if not create tmp_window and close, the `flameshot gui` won't exit after
+    // click copy button
+    QWidget* tmp = new QWidget();
+    tmp->show();
+    tmp->close();
 }
 
 // STATIC ATTRIBUTES

src/main.cpp

@@ -49,12 +49,14 @@ void requestCaptureAndWait(const CaptureRequest& req)
 {
     Flameshot* flameshot = Flameshot::instance();
     flameshot->requestCapture(req);
-    QObject::connect(flameshot, &Flameshot::captureTaken, [&](QPixmap) {
-        // Only useful on MacOS because each instance hosts its own widgets
+#if defined(Q_OS_MACOS)
+    // Only useful on MacOS because each instance hosts its own widgets
+    QObject::connect(flameshot, &Flameshot::captureTaken, [&](const QPixmap&) {
         if (!FlameshotDaemon::isThisInstanceHostingWidgets()) {
             qApp->exit(0);
         }
     });
+#endif
     QObject::connect(flameshot, &Flameshot::captureFailed, []() {
         AbstractLogger::info() << "Screenshot aborted.";
         qApp->exit(1);