Dark split-sword preview uses whatever previous melee weapon was selected

[Hippodoodle]

Dark split-sword preview uses whatever previous melee weapon was selected. I don't own the weapon, but when looking through my arsenal and browsing the various weapons, I noticed that the preview of my warframe holding it didn't change weapons, just it's stance. https://imgur.com/Kc7ziWP link to example pic since I can't seem to insert it through here.