Emoji rendered as all black with Cairo backend
I have a particular file, as attached, which is generated by entering an emoji in Google Doc, exporting it to PDF then cropping the page. It renders file in Acrobat and macOS Preview, but if I were to use
pdftocairo this way:
pdftocairo input.pdf -pdf output.pdf
Then the output shows a black glyph instead of the intended colour glyph.
The same happens if I were to print to a Cairo context with
poppler_page_render_for_printing_with_options, etc. So, I think the problem is within CairoFontEngine, possibly
This happens on Poppler 0.74 with Cairo 1.16, and I have verified that otherwise drawing emojis with PangoCairo works fine.