A trick when it's in the alpha channel is simply to CTRL+Click on the alpha channel's small preview to select it and then create a mask on the layer with the black background from the selection. (Then you can delete the alpha channel)
A trick when it's in the alpha channel is simply to CTRL+Click on the alpha channel's small preview to select it and then create a mask on the layer with the black background from the selection. (Then you can delete the alpha channel)