Prowler's profit is not listed in my list of active effects

[Kernel39]

I completed the no stone unturned quest and returned the helm of barenziah to vex in the thieves guild, but the "prowler's profit" perk is not listed in my active effects.

 

Is this just a bug and the perk actually is working?

[JRCosta]

There is a fix for the missing effect in the Unofficial Skyrim Patch ; according to UESP page:

 

• The Prowler's Profit may not appear in the Active Effects menu, but it should still be in effect.
  •  This bug is fixed by version 1.3.0 of the Unofficial Skyrim Patch.