Steps to reproduce the issue

Enable the sending of Action Log entries to a Super Admin by Mail in Joomla 3.9
Generate a load of emails

Expected result

Each subject line to be descriptive of the alerted action

Actual result

Generic "Latest User Actions" subject line

Additional comments

Trust me, myJoomla.com has been sending these kind of User Action Emails for years now and in the early days the number one complaint was that the subject lines were the same.

Also "Latest User Actions" is not actually what the email is about, its about a SINGLE user action generated - not plural.

Highly recommend putting the site name or url in the subject too

Remember, Super admins will want to filter these into other mailboxes - trust me...

If the emails are not useful, then no one will ever use this feature.

Recommend something like

• [MySite Name] User admin saved the global configuration
• [MySite Name] User mike logged into the administrator