I occasionally see posts that contain repeated blocks of text, and although I've encountered frequent problems with copy/paste functionality when writing a post, I'm careful to use the "preview" function first to clean things up, if necessary, before posting.
But I just saw a scenario in which I pasted text into a message post and it didn't appear in the post window, so I did it again, then I pasted the clipboard contents to another application, copied it to the clipboard in that application, then pasted it into the post window again, and it still didn't show up there, and then I clicked on the "preview" function and low and behold there were 3 copied of the pasted text displayed there! Now I know why I've seen all of those posts that contained duplicated text.
So until the software problem is fixed, the workaround seems to be to always use the "preview" function and edit the post text there before submitting it.
By the way, this problem seems to occur when using current versions of either Netscape or Internet Explorer.
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