The /effect command dose not work. I know i am doing it right. It shows the effect however if i do say jump boost effect even if i put the strength to 255 it has no effect. Haven't tested any other command.
Update: Ok it seems to work, however when doing something like jump boost strength 255 it doesn't want to work. This ticket has already been submitted. Do not work on this ticket. It is a dupe from MC-10755