issue #10922 Doxywizard Font Size Rendering Problem on 4k HiRes Monitors

Based on the comment https://stackoverflow.com/a/48582594/1657886 the code has been adjusted.

Author: albert-github

addon/doxywizard/doxywizard.cpp

@@ -807,6 +807,14 @@ void MainWindow::outputLogFinish()
 //-----------------------------------------------------------------------
 int main(int argc,char **argv)
 {
+  static const char ENV_VAR_QT_DEVICE_PIXEL_RATIO[] = "QT_DEVICE_PIXEL_RATIO";
+  if (!qEnvironmentVariableIsSet(ENV_VAR_QT_DEVICE_PIXEL_RATIO)
+        && !qEnvironmentVariableIsSet("QT_AUTO_SCREEN_SCALE_FACTOR")
+        && !qEnvironmentVariableIsSet("QT_SCALE_FACTOR")
+        && !qEnvironmentVariableIsSet("QT_SCREEN_SCALE_FACTORS")) {
+    QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
+  }
+
   QApplication a(argc,argv);
   int locArgc = argc;