>tree -if | grep -i "GRF$" |sed -n -e 's/\.\///gp' > newgrf.cfg

ottdc_grfpack/ca/canset/cansetw.grf
ottdc_grfpack/cs/csdset/csdseto.grf
ottdc_grfpack/cs/rail-cs/rail-cs-ottd.grf
ottdc_grfpack/de/dbsetxl/dbsetxlw.grf
ottdc_grfpack/de/gertrams/gertramsw.grf
ottdc_grfpack/de/tramtrk/tramtrkw.grf
ottdc_grfpack/def/4LV/4LVw.grf
ottdc_grfpack/def/ae_city/ae_cityw.GRF
ottdc_grfpack/def/ae_rura/ae_ruraw.GRF
ottdc_grfpack/def/ae_subu/ae_subuw.GRF
ottdc_grfpack/def/basic_platforms/basic_platformsw.grf
ottdc_grfpack/def/brickfreight/brickfreightw.GRF
ottdc_grfpack/def/buffers/buffers.grf
ottdc_grfpack/def/cantilever/cantilever11static_260.grf
ottdc_grfpack/def/harbour/harbourw_456.grf
ottdc_grfpack/def/jcindsta/jcindstaw.grf
ottdc_grfpack/def/modernsuburban/modernsuburbanw.GRF
ottdc_grfpack/def/newbridges/newbridgesW.GRF
ottdc_grfpack/def/newships/newshipsw.grf
ottdc_grfpack/def/newstats/newstatsw.grf
ottdc_grfpack/def/ngrails/ngrailsw.grf
ottdc_grfpack/def/pb_av8/pb_av8w.grf
ottdc_grfpack/def/pb_viaduct/pb_viaduct.grf
ottdc_grfpack/def/planeset/planesetw_459.grf
ottdc_grfpack/def/platforms/platformsw.GRF
ottdc_grfpack/def/stolentrees/stolentreesw_162_108.grf
ottdc_grfpack/def/tramtsg/tramtsgw.grf
ottdc_grfpack/def/ttrs3/ttrs3w.GRF
ottdc_grfpack/def/ukwaypoints/ukwaypointsw.grf
ottdc_grfpack/jp/hirotram/hirotram_w_987.grf
ottdc_grfpack/jp/japanset/japansetw.grf
ottdc_grfpack/jp/jpset_bld/jpset_bldw.GRF
ottdc_grfpack/jp/jpset_lnd/jpset_lndw.GRF
ottdc_grfpack/jp/jpset_tre/jpset_trew.GRF
ottdc_grfpack/jp/jpstats/jpstatsw.grf
ottdc_grfpack/na/pb_nars/pb_nars.grf
ottdc_grfpack/nl/dutchcat/dutchcatw.grf
ottdc_grfpack/no/nsbset/LangNor.grf
ottdc_grfpack/no/nsbset/nsbsetw.grf
ottdc_grfpack/old/newwaterw_412.grf
ottdc_grfpack/old/pb_av8w.grf
ottdc_grfpack/sr/srvtb/srvtbw_697.grf
ottdc_grfpack/sr/srvtt/srvttw.grf
ottdc_grfpack/t2m/T2MarsBonus/T2MarsBonusW.grf
ottdc_grfpack/t2m/Toyland2Mars/Toyland2MarsW.grf
ottdc_grfpack/tropic/troprs/troprsw.grf
ottdc_grfpack/uk/pb_hovs_bus/pb_hovs_bus.grf
ottdc_grfpack/uk/pb_ukrs/pb_ukrs.grf
ottdc_grfpack/uk/ukrsap1/ukrsap1w.grf
ottdc_grfpack/us/usset/ussetw.grf
ottdc_grfpack/us/usstats/usstatsw.grf