But what do original site and clone even mean in such contexts?
A clone is a complete copy, a double. Can we talk about the forum doppelgänger? What's cloned there? Name, design? So what? The main thing on the forum is people, questions and answers. But no one copies it... It seems strange to me to look for the original and clones among the forums, sometimes a copy can be better than the original, am I wrong?