I don't know beans about developing Firefox extensions, but Stuart Hamilton's right-click subscribe-in-Newsgator extension was much welcomed over here where it seems like we're looking for any available reason to lapse back into IE.
Somewhere around Firefox 0.9 the extension broke. Changing the following lines in ngsubscribe.js seems to get it back on track.
// GC: winhooks deprecated for cross-platfom shell service
//const lfContractID1 = "@mozilla.org/winhooks;1"
//var reg = Components.classes[lfContractID1].createInstance(nsIWindowsRegistry);
const lfContractID1 = "@mozilla.org/browser/shell-service;1";
var reg = Components.classes[lfContractID1].getService(Components.interfaces.nsIWindowsShellService);
Modified xpi file is zipped up here. Web server doesn't like raw xpi, go figure. Tested only on XP SP1 with FF 0.9.0 and 0.9.2, completely caveated with a standard “it works on my machine” disclaimer, ymmv.
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