Fixes #538 multiple window frames on windows

src/common/Singleton.hpp

@@ -0,0 +1,23 @@
+#pragma once
+
+#include <boost/noncopyable.hpp>
+
+namespace chatterino {
+
+class Application;
+
+class Singleton : boost::noncopyable
+{
+    virtual ~Singleton() = default;
+
+    virtual void initialize(Application &application)
+    {
+        (void)(application);
+    }
+
+    virtual void finalize()
+    {
+    }
+};
+
+}  // namespace chatterino