I assume this (legendary focus) is a guaranteed drop, as it has flavor text. I got it sometime during Scion of Blasphemy.
I can’t mark it at all in my inventory - if I hit space my character evades. But it’s just this item; I checked others.
Wouldn’t matter except I’d like to use it but it says I can salvage it for a new look, so not being able to favorite is risky business, please fix.
EDIT: This also happens with the five items Ormus gives you at the end of his chain.