I don't know if this is a bug but it seemed strange to me when it happened.
So I unlocked Cloak Mk II and went to buy it. I then bought one upgrade for it (Durability or whatever it's called). When I went to equip it I don't equip Cloak Mk II then equip the durability as an insert (like armor inserts), I just equip durability as my ability. This kind of worries me because it makes it seem like I never needed to buy Cloak Mk II but just needed to buy an upgrade for it. If this is unclear I can post screenshots when the servers come up later today. Thanks!