Notification for downloading a shared file

Hello,
We are beginning to use Nextcloud for sharing files with clients. Our clients are guests users on our nextcloud. We have set-up notifications of activities. We receive mails when a client upload a file on his shared folder. Thats fine.
But is there a way to be notified when a client download a file from the shared folder?
Apparently this is possible for files shared via link or mail (choice " A file or folder shared by mail or by public link was downloaded" in the settings of activity), but I have not found how to obtain these notifications when a registred user download a file.
I have found at least two post on the forum asking the same kind of features, but they are without answer…