[Development] Qt6 source changes

[Kevin Kofler]

Lars Knoll wrote:
> I’ve tried a bit and for most use cases where the list and the object are
> of reasonable size (e.g. 4*sizeof(ptr)and ~100 items in the list) that
> overhead is actually just as large.

4*sizeof(ptr) (i.e., at most 32 bytes) is not a large object. (Won't even 
the new QString with SSO be larger than that?) A large object is more like 
100+ or even 1000+ bytes.

        Kevin Kofler