Comment 3 for bug 394266

> The reason pages 1 and 4 of your PDF are printed as a bitmap are:
>
> - Firefox is using cairo operators that are not natively supported by PDF on
> page 1 and 4. I don't think there is any reason that Firefox needs to use
> anything other than CAIRO_OPERATOR_OVER when printing so I consider this a bug
> in Firefox.
>
> - As a result cairo embeds a fallback image in the PDF for the region drawn
> with operators not supported by PDF. But the bounding box of the PDF pattern
> used to draw the fallback image is set to the page size instead of the image
> size. This is a bug in cairo.
>
> - When poppler is used to print the PDF via the cairo backend the image becomes
> a full page image due to the pattern bounding box being set to the page size."
>
> It's also reproducible with git master version of poppler.

So, if I understood correctly, it's a bug in firefox and cairo, not in poppler, since we are using the wrong bounding box becuase of the cairo bug.