opening substack as modal unexpectedly calls openStack of mainstack

[Nicolas Cueto]

Hello List,

Here's the story. During the mouseUp of a mainstack button, a substack gets
opened as modal. However, soon as that substack appears onscreen, debugging
shows that the "on openStack" of the mainstack's stack-script has
(unexpectedly!) been called.

I guess this is happening because the substack has no script anywhere for
handling the openStack message, and thus this message is being passed on up
to the mainstack itself?

How do I prevent the substack's opening from making this unwanted call to
the mainstack's "on openStack"?

Thanks.

Cheers,
Nicolas Cueto