hi, i've got a problem with masking in fusion.
i added an image , conected it to luma keyer and then i conected it to the image plane and i've got this:

everything is ok, but when i tried to remove this sharp edges on left, right and below using a mask i've got this :

and when i render this i have this black frame on my composited image.
everything is connected like in this picture :

what should i do to remove this black frame ?
sorry for my bad english
edit :
ok, i found the solution.
i connected mask to the incorrect input. i should connect mask output to the garbage mask input
