Index: sources/main.h
===================================================================
diff -u -r781e62c996e81897517fbdb1bc79fe3bbcf165c1 -r5963f00ffd2c557d3ae06a5deea05032a3a3bd68
--- sources/main.h	(.../main.h)	(revision 781e62c996e81897517fbdb1bc79fe3bbcf165c1)
+++ sources/main.h	(.../main.h)	(revision 5963f00ffd2c557d3ae06a5deea05032a3a3bd68)
@@ -19,13 +19,19 @@
 
 // Qt
 #include <QObject>
+#include <QThread>
 
 // Project
 
 #define SINGLETON_DECL(vCLASS)                      \
 private:                                            \
     static vCLASS *_instance;                       \
     explicit vCLASS(QObject *parent = nullptr);     \
+    virtual  ~vCLASS() {                            \
+        delete _instance;                           \
+    }                                               \
+    vCLASS(vCLASS const &) = delete;                \
+    vCLASS & operator = (vCLASS const &) = delete;  \
 public:                                             \
     static vCLASS *I() {                            \
         if   (!_instance)                           \