New Post Icon

I understand the icons for the new posts and not new posts - but what does the envelope with a black dot in the middle mean?
Hi Joanna,

This is a useful icon which shows you at a glance which threads you have posted to. If you have participated in a discussion sometimes it can be difficult remembering which ones so this is a good memory jogger.

Regards, Mike
a black dot means you have posted to that thread, red means that the thread is popular .. I am not sure how many times read before it changes to red
"hot" threads are described down the bottom of the thread list for a particular forum. At the moment this is set to:

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