Does this GFCI need a sticker for code-compliance?
The NEC in 250.130(C) now requires extending an Equipment Ground Conductor to the grounding system when making an extension of a two-wire circuit that does not have an EGC.
If your circuit was extended before the current requirement or was extended by local exception then the receptacle needs to be marked &quot; No Equipment Ground&quot; and the ground should be left disconnected.

406.4 General Installation Requirements (D) Replacements
406.4(D)(2) Non–Grounding-Type Receptacles. Where attachment to an equipment grounding conductor does not exist in the receptacle
enclosure, the installation shall comply with (D)(2)(a), (D)(2)(b), or
(D)(2)(c).
(a) A non–grounding-type receptacle(s) shall be permitted to be
replaced with another non–grounding-type receptacle(s).
(b) A non–grounding-type receptacle(s) shall be permitted to be
replaced with a ground-fault circuit interrupter-type of
receptacle(s). These receptacles or their cover plates shall be marked
“No Equipment Ground.” An equipment grounding conductor shall not be
connected from the ground-fault circuit-interrupter-type receptacle to
any outlet supplied from the ground-fault circuit-interrupter
receptacle.
(c) A non–grounding-type receptacle(s) shall be permitted to be
replaced with a grounding-type receptacle(s) where supplied through a
ground-fault circuit interrupter. Where grounding-type receptacles are
supplied through the ground-fault circuit interrupter, grounding-type
receptacles or their cover plates shall be marked “GFCI Protected” and
“No Equipment Ground,” visible after installation. An equipment
grounding conductor shall not be connected between the grounding-type
receptacles.
Informational Note No. 1: Some equipment or appliance manufacturers
require that the branch circuit to the equipment or appliance includes
an equipment grounding conductor.
Informational Note No. 2: See 250.114 for a list of a cord-and-plug-
connected equipment or appliances that require an equipment grounding
conductor.