🚀 go-pugleaf

Hi All,
I have my own document page item
Class
{
    kMyPageItemBoss,
    kSplineItemBoss,
    {
        IID_ISHAPE, kMyShapeImpl,
        IID_IPAGEITEMEVENTACTION, kMyPageItemEventActionImpl,
    }
}

How can I override functions from "Fitting" context menu for it?
I'd like to have only one item "Fit Frame to Content" in this menu and I want to resize my object by my own in this function.

Now my object disappears after launch "Fit Frame to Content" menu item.

I tried to add
IID_IFRAMECONTENTSUITE, kMyShapeContentImpl,
substitution, but my overridden functions (even constructor of MyShapeContentImpl) are not launched.

Any help will be very appreciated.