How to stop QuickInstaller from removing content

I found this issue by accident: Plone's CMFQuickInstaller attempts to remove all traces of products when uninstalling, such as skins, tools, but also content. The latter can be rather harmfull. Imagine you have a product that creates a basic structure for your site, your users fill this structure with all kinds of content and for whatever reason, you install the product (and reinstall afterwards): All your content is lost! Not just your "structure" but (logically) all content inside it!

This cleanup is implemented through "cascading", and you can prevent it from happening with the following method in your Extensions/Install.py:

def beforeUninstall(self, reinstall=False, product=None, cascade=[]):
    if 'portalobjects' in cascade:
        cascade.remove('portalobjects')

    return True, cascade