Does anyone happen to know of an equivalent of Photoshop's "Layer Mask from Transparency" function in Affinity Photo? It converts the transparency of a layer to a layer mask, and removes the transparency from the original layer. In PhotoLine this is achieved by creating a new layer mask based on alpha. In Gimp there's the option to transfer a layer's alpha channel to a layer mask when a new layer mask is added to a layer with transparency.
To be clear, this function removes the transparency from the original layer, and transfers the alpha channel data to a layer mask.
It's a very basic option, and ought to be possible somehow in Affinity Photo, but so far I haven't been able to figure out how to accomplish this. Help is very much appreciated: I've been fiddling around for an hour now, and it's probably so obvious that I am looking past it.