Changes since the last update: #2912 Use empty private dictionaries instead of removing them. #2918 Regression test for issue 2842 #2926 Adds optional Shift for zoom keybindings #2915 Added additional language #2903 Add support for blend modes. #2913 Removes isOS2Valid; resets fsType #2932 Fix the calculation of default vertical metrics #2920 Scroll the Thumbnail of the current page into view when exiting fullscreen mode #2935 Store references as pngs and write failures to separate png files. #2940 Use relative paths for ref images and copy refs. #2927 Fix issue with 'this' binding in PdfStreamConverter #2942 Add back cid cff font test. #2950 Ignore test snapshots directory. #2952 Implement "B5pc-H" CMap #2724 Handles embed tags via PlayPreview API #2953 Deal with negative vScale value #2936 Add basic support for transparency groups. #2959 Always separate the last segment of the format 4 'cmap' subtable #2954 Add MS built-in Japanese fonts to nonStdFontMap #2961 Stop the viewBookmark button from displaying nonsensical link during document load #2955 Add a console warning when JavaScript/AcroForm/XFA was found #2962 Adds PlayPreview API support to pdf.js/mozilla-central #2969 Fixes notificationBox on Linux #2968 Misc NameTree/JavaScript fixes #2916 Rewrite and refactor getVisibleElements() to make it more generic

Looks green on Try so far. https://tbpl.mozilla.org/?tree=Try&rev=22cbf4c57632