The component of a plastid thylakoid membrane consisting of gene products and protein complexes that are loosely bound to its lumenal surface, but not integrated into the hydrophobic region.
Synonyms:
exact_synonym:
extrinsic to lumenal leaflet of plastid thylakoid membrane; peripheral to lumenal side of plastid thylakoid membrane
narrow_synonym:
extrinsic to lumenal side of plastid thylakoid membrane