On Tue, 18 Dec 2018 20:27:58 +0100, Mike Wey wrote:

The destructor tried to remove the toggleRef that was already removed by
the opCast. While your application keeps working this could be a memory
leak.

Should be fixed in:
https://github.com/gtkd-developers/GtkD/commit/b38f70c6f02b8efc8107f7939b3336644267aa9c

Thanks Mike!

Antonio