TypeError for minStack property

[dlancer]

Master branch have a bug with TypeError for minStack property (strict mode web-build).

[felipemanga]

I've been testing this as a fix:
set minStack(value) {},

I haven't pushed it to master since I've made other fixes and I want to make sure it's stable first.

the setter gets called when copying properties from an old instance of the core to a new one.
The problem is that the minStack should be read-only and not get copied. That's why there wasn't a setter before.

Thanks for reporting the issue and for sending the PR.