Fist of Fire, question on some wiki reporting

A couple of wiki’s ( fextra life and fandom, the notoriously bad ones) are reporting that Fist of Fire gains a synergy with Claw Mastery of 4% increased damage per level.

Actual in game doesn’t list this at all, but I’m rather curious as to where the Hell this information is coming from that both seem to be pretty adamant about this non-existent synergy as even claw mastery’s listing in those wiki’s report it as well.

Is there some patch note of a hidden mechanic somewhere that isn’t being reported or is it just noting this as claw mastery grants 4% increased claw class damage per level and FoF has a physical-fire damage conversion?