I've had the Master Rahool Mask since October, with no way to discard or dismantle it ([url]https://imgur.com/a/a9yFy2E[/url]). I can't put it in my vault, so it's stuck taking up inventory space. I've both repaired and reinstalled Destiny 2 (PC) since the issue started, so it's not something on my end.
-
You can't dismantle it while you are wearing it.