"Open in PDF viewer" extension opens PDF files directly in your default PDF viewer application. To use the extension, right-click on a PDF link and select "Open in PDF viewer" item. The extension downloads the PDF file in your default downloads directory and then executes external command to open the downloaded file with your default PDF viewer like Adobe Acrobat Reader or FoxIt PDF reader.
Note that to execute OS level command, you need to install a native client. Native client installation guide appears on first usage.
For more info and bug reports please use http://add0n.com/open-in.html?from=pdf
In the FAQs page you can find all my "open in" extensions.
It is now possible to define left-click open in default PDF reader from the options page. If this mode is enabled, the extension blocks the default action when a link with the PDF mime type is the target.
It is possible to ask the extension to send the PDF URL to the external executable. Make sure your PDF Reader can open remote URLs before enabling this option