Hi guys,
I am using the sales hub app and notice there is a filter option "Followed" in the work list of Sales Accelerators.

What does the "Followed" mean?
I digged for days and find out there are something like "record wall" which is replaced by timeline(is that true?) .
I tried to configure the Activity Feeds Configuration but the Follow/unfollow is only available on User entity by default. I activated the Lead configuration and published the Lead entity.

There is no Follow/Unfollow button displayed in the command bar.

But there is a new View added to the view List.

You can see there is exactly a Follow button displayed in the command bar in a Youtube video(https://www.youtube.com/watch?v=Xw8uoHsPzE8)
Notice this video is posted at 2021/08/31.

What did I miss...? Or if the filter option "Followed" in the work list of Sales Accelerators is totally irrelevant to Activity Feeds?
Thank you !
Any answer or web resources are very appreciated!
Best Regards
Justin