Sorry for the OT, what is "TFA"?
It's a reference to RTFM, Read The Fine Manual.
TIL: RTFM was a phrase from the 40s : "Read the field manual."
Usually it's a kind of negative retort - 'well if you'd actually bothered to read TFA then ...' - but increasingly it seems to be used without such emotion (particularly, to me anyway, on HN) to mean simply 'the submission'.