https://developer.mozilla.org/en/Plugins
http://hudolejev.blogspot.com/2009/08/building-npruntime-sample-plugin-in.html
http://colonelpanic.net/2009/03/building-a-firefox-plugin-part-one/
http://colonelpanic.net/2009/12/memory-management-in-npapi/
http://git.webvm.net/?p=npsimple
Browser Plugins vs Extensions
http://colonelpanic.net/2010/08/browser-plugins-vs-extensions-the-difference/
Four part tutorial (MUST read for everyone trying to understand the NPAPI)
http://colonelpanic.net/2009/03/building-a-firefox-plugin-part-one/
http://colonelpanic.net/2009/05/building-a-firefox-plugin-part-two/
http://colonelpanic.net/2009/08/building-a-firefox-plugin-part-three/
http://colonelpanic.net/2011/07/building-a-firefox-plugin-part-four/
In linux,
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