Marking Cross-posted messages as Read

Why back when, maybe Mozilla Suite or even Netscape Suite, it used to be 
that if you clicked on a message that had been cross-posted to several 
newsgroups, that message would be marked as read in all those newsgroups 
that you subscribed to.

This function hasn't worked for a long, long, time and I miss that 
function-ability, especially on my UseNet server.

I had thought that the function could have been done using an 
"If/Then/Else" type loop working with the information contained in the 
Xref line of a messages header. Something like ....

If the Xref line doesn't exist don't do anything special
	If the Xref line exists then
		Go through the groups listed in that line and if I don't subscribe to 
the group, do nothing
			If I subscribe to those groups, then mark that message number as read 
in that News Servers ".rc" file group line as Read
			Done
		Done
	Done
Done

Today, I've been reading one of the Support newsgroups on the 
Eternal-September UseNet Server and mention was made that something 
similar could be done using the information contained in the 
"Message-ID" line (a line which, I think, SM doesn't handle at all!) in 
the message header to read "Mark as Read" messages that may have been 
posted to the same newsgroup but on totally separate News Servers. I 
don't know how, just mentioning this.

Reading that thread, however, has prompted me to ask ....

Is there still work being done on this "Marking Cross-posted messages as 
Read" function with-in Mozilla/ThunderBird/SeaMonkey or has lack of 
person-power seen it pretty well been put on the Back-Burner ... or even 
the Back-Back-Burner??

There you go .... Bug https://bugzilla.mozilla.org/show_bug.cgi?id=43278 
refers.
-- 
Daniel

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