The part that is dripping is an air vent/housing. It's probably leaking because the drain in the freezer is frozen or plugged up.
The water is coming from frost being melted off the evaporator coils during the defrost cycle. Instead of the water draining down to the drain pan, its going sideways and coming out through the vent housing.
You'll need to figure out why the drain isn't draining and then you'll need to get rid of all the ice that has accumulated in the insulation.
Part number 17 is the part you show in your picture dripping water.
Parts for Frigidaire LGHT1846QE0: Shelves Parts - AppliancePartsPros.com
Your model number is missing a few digits. I used this number to look up your refrigerator.