Screenshot problem

[Gribouillis]

Why not use the canvas postscript method to save the canvas as postscript then convert the postscript image to another format?

Output:
help(Canvas.postscript)
Print the contents of the canvas to a postscript
        file. Valid options: colormap, colormode, file, fontmap,
        height, pageanchor, pageheight, pagewidth, pagex, pagey,
        rotate, width, x, y.

Also the pyscreenshot module says

The pyscreenshot module is obsolete in most cases. It was created because PIL ImageGrab module worked on Windows only, but now Linux and macOS are also supported.

An old trick to convert eps to postscript:

cv.postscript(file="circles.eps")
    from PIL import Image
    img = Image.open("circles.eps")
    img.save("circles.png", "png")

See also pillow image formats