If we use Qt5 5.13.0 to compile this program, QObject::trUtf8 is deprecated since source code assumed to be saved in UTF-8 and may cause compilation error. And in the file "Modules/AppUtil/src/QmitkSafeNotify.h", it has the uses of app->trUtf8 with only ASCII character inside it. So I want you to change these lines
(Line 53, 54)

msgBox.addButton(app->trUtf8("Exit immediately"), QMessageBox::YesRole);
msgBox.addButton(app->trUtf8("Ignore"), QMessageBox::NoRole);

into

msgBox.addButton("Exit immediately", QMessageBox::YesRole);
msgBox.addButton("Ignore", QMessageBox::NoRole);

Thank you in advance