Marking notifications as read/unread
This requirement, and the stickiness of the notification badge unless the user engages in extra steps - compared to the previous behavior, merely viewing the comment dropdown - generates unnecessary extra noise for the average user.
That may not be apparent from committed beta testers.
But as a regular user - SE is a Q&A feed - not a critical app.
Please keep the cognitive noise level down.
p.s. we can always look at the dropdown to see what we might have missed, so this is not fixing anything.