resolveOverprint property
Whether to resolve overprint (ยง8.6.7) against a colorant buffer rather than leaving the painting device to approximate it (issue #502).
On for painting and recording walks: on a page that actually enables overprint, every draw's colorants are tracked in a PdfOverprintCompositor and an overprinting draw is handed the sRGB the subtractive composite really produces, with its overprint flag cleared so the device paints it plainly. Off for consumers that never look at colour (text extraction, the image-collect scan), which would only pay for the buffer.
Implementation
final bool resolveOverprint;