In OJS 2 the editor could activate the link ‘Notify Users’ and tell all the registered users that a new issue was published. I can’t can’t find a similar option in OJS 3. Have I overlooked something?
OJS3 sends those notifications automatically when you publish a new issue. When you click “publish issue” the system will ask you if you want to notify users. However, there has been some discussion whether the notification the users get is too simple. See When publishing new issue, PUBLISH_NOTIFY template not used · Issue #3646 · pkp/pkp-lib · GitHub and [OJS] Publish Notify email template not used in OJS 3.0.2 · Issue #2406 · pkp/pkp-lib · GitHub
Not having a proper message mailed out on new issues being published is one of the many reasons why I as an editor-in-chief long for OJS 2.
I had assumed that going to OJS 3 would improve the layot possibilities of that important mail - but instead it has been replaced by an e-mail without any contents, with a subject that is too imprecise to get recipients to read the mail - and a general layout that more looks like spam. And the discussions referred in the answer above is from spring 2017