This bug with the shadow power (apprentice / master / novice) happened to me first last week (started at the previous traversal encounter), and then this week it happened after I got to the final boss. Two attempts, two weeks in a row. I've run into this issue where I am attempting Flawless and get all the way to the final boss, and then the Shadow buffs no longer work properly. You can in the video link attached, see I step into the Shadow buffs but there is no tracker at the top. And then when I do get full power, I still can't swap using the Renegades button ('Z" on PC). I was able to temporarily fix it but doing the 'Compel' ability on the boss, as you can see in the video (https://www.youtube.com/watch?v=N2rg10Pqh58), but then when picking up the buff again, you can see it still doesn't track. This is ruining my flawless attempts because I can't properly track or swap between abilities. You can also see another bug where my weapon becomes invisible at one point.