The idea of the message is to remind you to keep you active on the forums you dont have to make a new post you can reply to someone else post. Im not 100% sure but you could probably just say Hi in chat box or rep someone. The point is to keep you interacting and making friends rather than sitting back wondering why people dont talk to you. Its easy to forget how inactive you can get if you do a lot of reading.
The point of the message is to encourage forum participation. It happens if you don't post every 3 weeks and you can just ignore it anyway not a biggie.
Don't see why you had to make a useless thread when you very well could have spent the same amount of time to post something in one of the threads you do read.
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