Please double check. The installer and the updater both don't touch the user's profile so it is extremely unlikely that the add-on was by removed by either of them. It is possible that the add-ons manager code which does have code that touches the extensions in the user's profile could have removed it.
Please double check. The installer and the updater both don't touch the user's profile so it is extremely unlikely that the add-on was by removed by either of them. It is possible that the add-ons manager code which does have code that touches the extensions in the user's profile could have removed it.