→ Pause Notifications

Press the Option key while clicking on the Notification icon in the right end of the menu bar. This will pause the display of notifications. To reactivate them, you can either Option-click the same icon again; display notifications at the right of the screen by clicking on the Notification Center icon, then toggle the Show Alerts and Banners switch from Off to On; or just wait until tomorrow, when they’ll go back on automatically.

Nice. Thank you Macworld and Macworld Hints reader guillaumegete