Comment 15 for bug 1037956

@Bertrand Grégoire - besides the gradient issues with certain cairo versions, the file 'flyer.svg' has additional issues when exporting to PDF: the filter effect 'Invert' applied to the group used as mask is not applied when exporting to PDF (see also comment #3 in bug #808898). The workaround to mask with a bitmap copy of the filtered group did produce visually similar results in the PDF though.