Julian, seems like a windows issue.

Assigning to Lei as a printing issue.

Able to reproduce this issue on Windows 10 with #63.0.3239.132 and also in earlier version #60.0.3112.0.

This is a non-regression issue, marking it as untriaged

Attaching the screen-cast for reference.

Note: unable to test this issue on Mac & linux due to the lack of GPO policy setup.

Deleted: 805926.mp4 2.4 MB

	805926.mp4 2.4 MB View Download

Any update since?
Does it mean there no solution ?
How can we handle it ?

No updates, but this is definitely reproducible, so we'll try to fix it.

I think this broke with r468370. A temporary workaround would be to flip "Disable PostScript Printing" to "Enabled" in chrome://flags. Can you try that and see if setting the flag fixes your problem?

If you have this problem, it will be helpful to know what printer plus driver combination is affected. At least on my Windows 10 computer, the "Microsoft Print to PDF" virtual printer does not have a color setting at all. I'm not sure which "Microsoft PDF maker" the original bug reporter was referred to.

Also, the original bug reporter mentioned a problem with "Adobe PDF maker" - please file a separate bug report for that and mention the exact name and version of the Adobe virtual printer.

Based on comment 4, I can reproduce the problem with the CutePDF virtual printer, which is PostScript-based. I also tried a HP LaserJet 2500 PS, and for the HP printer, the output differs when the color/monochrome setting gets toggled.

My guess is CutePDF expects the input to be in monochrome already, whereas other drivers may be smart enough to change that themselves. Maybe Chromium has to render to grayscale as well, and not rely on the printer driver to do it.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/5c500489a0675663b2163bdbf3ba94f49b4771de

commit 5c500489a0675663b2163bdbf3ba94f49b4771de
Author: Lei Zhang <thestig@chromium.org>
Date: Thu Apr 12 07:34:16 2018

Add a use_color field to PdfRenderSettings.

Set it properly in callers that require PDF rendering, and read it in
PDFiumEngine to pass the right rendering flags to PDFium.

BUG= 805926 , 824643 

Change-Id: Ia2e8a22259bef1ca78fe425592eeb407bbc4ba35
Reviewed-on: https://chromium-review.googlesource.com/1000555
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Reviewed-by: Rebekah Potter <rbpotter@chromium.org>
Reviewed-by: Jianzhou Feng <jzfeng@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#550078}
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/chrome/browser/printing/cloud_print/privet_http_impl.cc
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/chrome/browser/printing/pdf_to_emf_converter_browsertest.cc
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/chrome/browser/printing/print_job.cc
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/chrome/browser/printing/print_preview_pdf_generated_browsertest.cc
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/chrome/browser/printing/pwg_raster_converter.cc
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/chrome/browser/printing/pwg_raster_converter.h
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/chrome/browser/printing/pwg_raster_converter_browsertest.cc
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/chrome/browser/ui/webui/print_preview/extension_printer_handler.cc
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/chrome/service/cloud_print/print_system_win.cc
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/chrome/services/printing/pdf_to_emf_converter.cc
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/chrome/services/printing/pdf_to_pwg_raster_converter.cc
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/chrome/services/printing/public/mojom/pdf_render_settings.mojom
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/chrome/services/printing/public/mojom/pdf_render_settings_mojom_traits.cc
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/chrome/services/printing/public/mojom/pdf_render_settings_mojom_traits.h
[add] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/chrome/test/data/printing/bug_767343_mono.emf
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/headless/lib/headless_web_contents_browsertest.cc
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/pdf/pdf.cc
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/pdf/pdf.h
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/pdf/pdf_engine.h
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/pdf/pdfium/pdfium_engine.cc
[modify] https://crrev.com/5c500489a0675663b2163bdbf3ba94f49b4771de/printing/pdf_render_settings.h

Please try 67.0.3396.0 or newer and see verify this is fixed. One can probably install Google Chrome Canary in a day or two and get that version.

As mentioned in comment 8, please file bugs if you have other issues.