Bug: FF does not render visible portion of layer

I have a layer in Photoshop CS6 that extends beyond the canvas area. When I process this layer with FF Pro 4, what happens is that FF does not process the pixels that are visible on the canvas, but it starts processing an area of the correct size beginning with the top left of the layer, regardless of which pixels on the layer are visible on the canvas.

This means that some of the visible pixels on the right hand side of the layer are not processed

Even creating a layer mask does not help - the layer mask is ignored and processing begins with the top left of the layer.

The only way I could work around this was to crop the layer down to the size of the canvas.

Could this be corrected in a future build?

Thanks
Richard