Not sure if it was always like this, but I've recently found that in wanting to review posts or situations I've been interacting with / subscribed to notifications on, I'm unable because after going to see it once, I can't go back to respond or engage via the notifications pop-up panel.
Whatever the design philosophy is, I'm open-minded about it, but please don't make the notifications disappear!
I miss them. ❤
You can just format them to show they've already been seen, any number of ways.
Thanks.