Ever fought your way up and down half a dozen towers of the Endless Citadel only to find your Quantum/Omen Sight had expired?
Quomen is a very simple addon for artifact hunters that displays a text warning when your Twisted Artifact Buff has expired.
Note: I play Guardian, so testing done with Omen Sight, but it should work for Defiants as well. If it doesn't I'm sure I'll hear...