I have a stand-alone xulrunner application, that needs extension to work properly. But after I install xpi file, my jsconsole is reporting me an error "Failed to load overlay from chrome://my-client/content/overlays/index.xul". That means that chrome.manifest file is recognized, but the path to overlay is not good.
My chrome.manifest file in xpi
content my-client file:chrome//
overlay chrome://app/content/lib/conf.xul chrome://my-client/content/overlays/index.xul
Id of extension in install.rdf file is the same as the id in application.ini file of the main application. I have enabled extension manager
[XRE]
EnableExtensionManager=1
And I have extension.js file in my prefs.
The weird part is when I just symlink folder of my-client extension into extension folder in my main application everything works just as i expect. This only occurs when i install xpi through extension manager.
I figured it out. The problem was that I forgot to put this line of code in my install.rdf file
<em:unpack>true</em:unpack>
documentation here: https://developer.mozilla.org/en/docs/Install_Manifests#unpack