Darkshrine in lab working but not displaying

In both my Cruel and Merc labs I touched several Darkshrines, and at least one of them in each run didn't display in the blue description under the minimap, while the others (like "additional unique" and "brutal shrine") did.

On Merc I'm sure the one not showing was "Additional enchant font use", because I got to use it twice. Not sure which one it was on Cruel.