This is a bug that has existed since vanilla I believe. It was that common for me, I just assumed somebody would have reported it by now, but evidently not.
I believe the invoking factor and problem is that as the turn processing is ending, I am able to attack enemy units in range by clicking individual cities before the notifications of my ability to attack them appear and if I do not wait for the notifications to appear and the turn to fully end, the notifications will persist until the end of the game and are not removed when starting the next turn.
It pretty much ruins the usability of the notifications bar. If you cannot reproduce it, I'll get a recording of it for you.
I believe the invoking factor and problem is that as the turn processing is ending, I am able to attack enemy units in range by clicking individual cities before the notifications of my ability to attack them appear and if I do not wait for the notifications to appear and the turn to fully end, the notifications will persist until the end of the game and are not removed when starting the next turn.
It pretty much ruins the usability of the notifications bar. If you cannot reproduce it, I'll get a recording of it for you.