Use leaveEvent instead of checking mouseMove position constantly.

lib/gui_lite.py

@@ -402,8 +402,7 @@ class PasswordDialog(QDialog):
 
 class ReceivePopup(QDialog):
 
-    def mouseMoveEvent(self, event):
-        if not self.rect().contains(event.pos()):
+    def leaveEvent(self, event):
         self.close()
 
     def setup(self, address):