I would like draw blue lines onto a TImage, which is a child object of a ScrollBox. But when I drawing, it always shows the black background canvas rectangle under the blue lines. I would like see only the lines without the black background rectangle. Can I do a transparent TImage from it?

How is it possible in Lazarus(linux) to get a window handle knowing the PID of a third-party process in Linux. Perhaps an analogue of the function for Windows enumthreadwindows