errors from terminal (Ubuntu/firefox24)

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Where can I place this error message? I had an answer before but lost the e-mail!

error: ghostery: An exception occurred.
TypeError: Ghostery.BlockingPolicy.cookieManager is null
resource://firefox-at-ghostery-dot-com/ghostery/lib/background.js 506
Traceback (most recent call last):
File "resource://gre/modules/commonjs/sdk/system/events.js", line 62, in Observer, line 506, in Ghostery.BlockingPolicy.cookieBlockingPolicy
Ghostery.BlockingPolicy.cookieManager.remove(cookie.host, cookie.name, cookie.path, false);