Disabling Player Unit Frame's Autofading

[whatisxml]

When leaving combat, the player unit frame quickly fades to about 0.5 alpha and then completely fades out a few seconds later. It's then unlinked from the player and can be used for other units' name plates.

I've been trying to figure out a way to prevent it from fading at all. At first I thought I could hijack the NAME_PLATE_UNIT_REMOVED event to avoid a call to OnNamePlateRemoved() in Blizzard_NamePlates.lua but that didn't have the effect I wanted.

I also tried messing with UIFadeIn() and UIFadeOut() but it seems to be fading using some other method. I also thought it was being added to the AddToAutoHide() list, so I set the UnitFrameXNamePlate.disableMouse=false but the Frame faded even while my cursor was hovering over it.

Any thoughts on how to keep the unit frame visible?
I'd prefer to use the built-in frame rather than remake my own.