OK, different tack here.
Both twitter and Facebook have single key shortcuts of their own for navigation. Also, for Facebook, each grouping of a post and its replies is in an article region. I am not sure if NVDA "d" key will skip to the next article or if it just uses more encompassing HTNL regions.
So if you are in NVDA focus mode:
j will move to next posting
k will move to previous posting
l will like a posting
? will give a full list of shortcuts I will include twitters list below.
BTW J/K/? also work in Gmail .
t in a twitter web page will retweet with an option to add your own text.
WindowEyes once had a training session on these keystrokes I wonder if VFO kept any of that training around.