Here is the facebook accessibility page:
https://www.facebook.com/help/141636465971794/

I went to the heading "Accessibility Basics", then arrowed down to the
button labeled "How can I navigate Facebook with keyboard shortcuts?". I hit
spacebar on that button. All of the keyboard shortcuts listed in that
section worked for me.

Of course, be sure to disable the Virtual PC Cursor with JAWSkey+Z.

I hope this helps.
-Paul