Have you ever wanted to mark all of the headlines inside a widget as read? You can now do this by holding the left mouse button down inside any widget and tapping the "X" key on your keyboard.
If you want to mark all widgets on your page as read, you can hold the left mouse button down in the empty space between two widgets, and tap the "X" key. Every widget on the current tab in your Protopage will be marked as read.
Please note it is important that you keep the mouse button held down while you are tapping the "X" key for this to work. This mark-as-read feature applies only to News Feed widgets, Twitter widgets and Email Inbox widgets.
If you need to reverse this and un-mark any items as read, you can do this for a particular widget or for the entire page by tapping the "S" key instead of the "X" key. Enjoy!