Around 15 maps from the map archive use the embedded RGB images. Basically no tileset included in Teeworlds maps will ever have no transparent pixels (top left tile is empty). I don't think this feature is pulling its weight (the extra complexity when parsing maps) and should be removed. It's currently not really a useful feature either because it depends on the source PNG format. If we were to embed grayscale images, we shouldn't extend the map format either, but rather convert these g...