Thank you a lot for quick and exact answer!

@Jeff-Andle

If you do not like that cleanup or if it is too hard to decide whether to free the memory you can use one oft these.

QSharedData QSharedDataPointer QSharedPointer

I have used QSharedDataPointer (but not the others so far), and it seems to work nice.

You're welcome !

If you have everything running now, please update the thread title prepending [solved] so other forum users may know a solution has been found :)