Just tried Krita out on Win7 x64 with 16-bit colors. It works fine with default white background. But if I set the background color to 0% opacity (aka transpar

Just tried Krita out on Win7 x64 with 16-bit colors. It works fine with default white background. But if I set the background color to 0% opacity (aka transparent) the drawing becomes ultra-slow like 1 pixel per second :/