Private messaging Module uninstalled on Upgrade to v2.24

A couple of changes have come up with upgrading to version 2.24 from 2.23. I have an earlier Topic on entity/field definitions needing updating ( Refer link:…) Another change i have seen is that the private messaging module gets uninstalled in the upgrade process to 2.24, so once done with updating ( am using composer dependant installation ) just do another composer update -vvv before running drush updatedb. Once installed run drush updatedb then updated cr and drush cron to finalize your update. Maybe admin can help us understand why the uninstall?