Fri, 22 May 2009 12:06:38 -0700, /Rufus/:
...Help says there is a "Customize" option to allow filters to use
headers not listed in the first drop down menu.
Where, and how?
It is not available for newsgroups filters with SeaMonkey 1.*.
It is available for newsgroups filters with SeaMonkey 2.0
* Allow to filter news based on any headers (Bug 16913)
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