It seems to me that during the night from January 16th to January 17th (okay, sometime between Jan 16th 20:00 and Jan 17th 9:00 CET) some of the posts on NetPro have disappeared. That night, I have made a response in the thread about WFQ:
When I came back in the morning to check on things, my reply has disappeared from the thread and the original poster indicated in his reply that indeed he cannot see my answer anymore (which suggests that he has seen it before, otherwise, he would not even know that it was me who answered). So I have posted my answer again but I am concerned about what really happened.
What is also interesting is that when I originally browsed this thread, there was the original post and then the first reply by the original poster himself who added a comment to his original question. That comment can be viewed here:
When I came back after a couple of minutes to write my first answer, I did not see this reply in the thread, and I have asked in my first answer whether the original poster has removed his post. Now, the situation got reversed - my first answer has disappeared and this comment has returned.
At some point the counter of 'replies' in Discussions tab was 1 less than the replies within thread. In my second post an 'unexpected error' page appeared. I tried to post again recovered version of my post 3-4 times, I got the same error, and my post doesn't show. The counter has increased a lot after my efforts, so maybe in the end I will get to see my post many times instead of one.
Let's hope that this post will appear now!
p.s. While I was writing my first post, the author of the thread posted a reply to the thread. Maybe this issue appears when people are trying to post simultaneously to the thread, maybe not. Just recalled this and thought it might help.
I have also noticed a strange behaviour where I open several tabs of various threads with Firefox. I use Google reader and often open multiple tabs for interesting threads. Then when I go to login via one of the tabs it changes the thread to one open in a different tab. This is very frustrating because then I can't find the original thread that I had opened.
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Thank you very much for looking into this and for being so prompt. I have not ecountered any similar problems since my original report here so I believe it has been corrected. In any case, should the problem reappear, I will certainly let you know.