Hi There @rogerwang!
I am having an issue with Print Preview on NW.js V 0.19 (win 32), My OS is Windows 8 and a screen shot can be seen attached below. The Print Preview Dialog says the following “NW.js does not include the PDF viewer which is required for Print Preview to function”. Any help would be appreciated to resolve this issue. I might have missed something and was not able to find a solution anywhere in the docs or over here.