In my community, I have set the approve unless trust level and approve new topics unless trust level to TL1, which means that TL0 posts needs to be approved. Then, I noticed that many TL0 users didn’t and still don’t know when their post gets approved or rejected and are often getting confused.
Therefore, I would like to propose a feature that will send a notification to the user, whose post pending approval and it has been approved / rejected / edited by a mod/admin.
Approved:
In the notification section, there can be a 👍 Approved notification, which will let the TL0 user know that their post has been approved and it has been posted.
Update: The Rejected and Edited isn’t something that has to be added, as it may annoy some users. You can scroll down though and check my suggestion
Rejected
Same thing, in the notification section there can be a 👎 Rejected notification and the user will understand that their post has been rejected.
Edited:
Same with the Approved, with only addition → an automated message from @system that will state what has been edited and who edited it. Example
Title: Post / Topic has been approved, but edited
Topic body: This is an automated message from discourse to let you know that your topic / post, that was pending approval, has now been approved, but edited by:
@name - edit
Let me know what you think or if it has already been proposed. Sorry if it’s in the wrong category, my first time proposing something. 
وهذا أمر محبط.