We have a good feeling this will be a quite 'easy peasy' task.
When a user publishes a post, then in the top right corner of that post, if you click on the '(...)' icon, then a drop-down list will pop up.
Please select the 'Follow Post' option from that dropdown.
A screenshot can also be found below.
Finally, the following image will also pop up, to signify that you are successfully following it.
What is the benefit of following a post?
Whenever there is a thread post interaction or update from the post you are following, you will always be notified.
