Tap the Facebook app icon, which resembles a white "f" on a blue background. If you're logged in, doing so will open your News Feed. If you aren't already logged into Facebook, type in your email address (or phone number) and password, then tap Log In. It's the bell-shaped icon at the bottom of the screen. This will open a list of your notification history It's the three horizontal dot icon on the right side of a notification.This will prompt a pop-up menu to appear after a moment. You can also tap and hold on the notification instead. It's in the pop-up menu. Doing so will delete the notification from the "Notifications" menu and the activity log. You can repeat this process for each notification you wish to clear.

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Write a summary of the previous text in Vietnamese:
Mở Facebook. Chọn biểu tượng "Notifications" (Thông báo) hình chiếc chuông ở bên dưới màn hình. Chọn ⋯. Chọn Hide this notification (Ẩn thông báo này) trong trình đơn vừa hiển thị.