It's still not clear to me why it is so difficult to introduce this option...we've even too many different choices for hotkeys, but "do not disturb" is still missing...I was enjoying a power nap just after lunch, and I forgot to enter the "do not disturb" state using the quick app ring; well, I've received many notifications, but I was in that semi-unconscious state where if you make any movement and concentrate on doing something you have lost the moment and the nap is over. in this case, without looking at the clock, simply by pressing a hotkey I could silence it entirely and enjoy the moment. This is just one example of a situation where I would have liked to have a hotkey for it, but I would have many others, even in the workplace.