Made addon propertie function final, fixes cover addon properties
Made addon propertie function final, fixes cover addon properties

davidhesselbom/rock,fredrikbryntesson/rock,jonathanudd/rock,magic-lang/rock,kirbyfan64/rock,cogneco/rock,fasterthanlime/rock,magic-lang/rock,marcusnaslund/rock,davidhesselbom/rock,thomasfanell/rock,jonathanudd/rock,ds84182/rock,ooc-lang/rock,kirbyfan64/rock,shamanas/rock,ds84182/rock,thomasfanell/rock,shamanas/rock,fredrikbryntesson/rock,ooc-lang/rock,zhaihj/rock,fasterthanlime/rock,zhaihj/rock,marcusnaslund/rock,cogneco/rock