Facebook used to have a "mark as read" button that would appear while hovering the mouse over an unread notification. Now, instead of that, I see an ellipsis with options to "Hide this notification" or "Turn off notifications about this post".

There is just the "mark all as read" link at the top.

Is there a way to mark a single notification as read?

Note that I am using the website in Chrome, not the mobile app.