geranylfarnesyl diphosphate synthase activity https://github.com/geneontology/go-ontology/issues/20661 https://github.com/geneontology/go-ontology/issues/29264 RHEA:25694 GO:0044687 Catalysis of the reaction: (2E,6E,10E)-geranylgeranyl diphosphate + isopentenyl diphosphate = (2E,6E,10E,14E)-geranylfarnesyl diphosphate + diphosphate. jl MetaCyc:RXN-8813 FGPP synthase activity 2012-08-15T14:20:25Z molecular_function EC:2.5.1.81 prenyl diphosphate synthase activity