Embedding NPAPI plugin in background using just Firefox Addon SDK
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I have recently developed a NPAPI plugin (using FireBreath) in combination with a Google Chrome Extension. I am embedding the plugin using the  *background.html* page and access it from **multiple** extension pages. Thus, the plugin remains loaded in the background page (until the extension is unloaded or the browser is closed).

I am now searching for the easiest way to port this extension to Firefox. Using the Addon SDK and it's API, i can reproduce the communication between the addon code and HTML user interface.

As there is no such global background DOM as in the Chrome Extension, how would I load the NPAPI plugin just once, without inserting it in every page of the app UI?

I've seen that using a [XUL overlay][1] would allow that - is there a way using just the addon sdk?


  [1]: http://stackoverflow.com/questions/7458530/cannot-access-npapi-functions-in-firefox-extension "a XUL overlay"