<Separating out Ideas submissions with multiple items>
There could be scenarios such as – an application INI file contains Localhost address which is dynamically written at the time of application deployment
Understanding the purpose of MSIX, which is to eliminate the necessity to have custom actions, scenarios such as above turn out to be challenging without installation time actions
Having Post-Install script execution supported in MSIX will ease its adaptation for minority of applications as well which required such customization