Many Facebook users are not aware of the keyboard shortcuts FB provided for their users. I have listed few keyboard shortcuts below, among them few are browser dependent but not all.

Friend requests Page [Browser Dependent]

Internet Explorer for PC: Alt + #, then Enter

Firefox for PC: Shift + Alt + #

Safari for Mac: Ctrl + Opt + #

Firefox for Mac: Ctrl + Opt + #

Chrome for Mac: Ctrl + Opt + #

Chrome for PC: Alt + #

Keyboard Shortcuts 

c - Comment when on a story in News Feed

j and k - Scroll between News Feed stories

l - like or unlike a selected story

q - search for a friend to chat with

p - Focus on the text box when making a post

/ - Search

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