Greg's browserfeedwriter javascript finds TBB's full path on Windows
http://pseudo-flaw.net/tor/torbutton/browserfeedwriter-error.html
Shondoit went there using TBB on Windows and it said "found location: "file:///[...]/Tor%20Browser/FirefoxPortable/App/Firefox/components/FeedWriter.js" where [...] is his install location.
Reported at https://blog.torproject.org/blog/new-tor-browser-bundles-17#comment-15627
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