Warframe - Critical Focus & Stagger Weapons (Mechanics Explained & Tested)
I'm not sure how all of this got started. Possibly a bug at a certain point but bottom line is that Critical Focus does work on weapons that have a stagger or knock-back effect.
Warframe is a free-to-play cooperative third-person shooter video game developed and published by Digital Extremes. Originally released for PC Microsoft Windows in March 2013, it was later ported to the PlayStation 4, Xbox One, and Nintendo Switch.