Black and white/monochrome mode is unimplemented in Paint for ReactOS

Open up Paint for ReactOS, open the "Image", menu, click "Attributes...", click "Black and white", click "OK". Nothing happens, and the setting doesn't even stay selected. The expected result is a warning dialog pops up, and when you press "OK", the image gets converted to black and white/monochrome, and the color palate gets swapped for a halftone palate. Related to CORE-15979, but I can't link issues anymore.