As of this week, the X-notifier Facebook script no longer works in Google Chrome. It always shows as red (unchecked). The script was last updated on March 10, 2014, so perhaps Facebook's security and/or layout has changed recently causing the script to fail. Judging from forum post (http://xnotifier.tobwithu.com/dp/node/2848), this does not seem to be an isolated issue. Users have reported it broken on both Chrome and Firefox, although it works on FF for me for some reason.
A man should.
A man has.
Valar Dohaeris.
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Duplicate post, by the way.
And the developer is the same for both.