When I was looking for an answer for my question Why does 1,4-diiodobenzene have a non-zero dipole moment? asked on the main site (a few days ago), I came across 'exactly' the same question posted on a different forum on the same day. To double check this observation, I looked for the question What single, pure compound would best replace petrol? asked on the main site (in the year 2017) to be also copied there. But it is dated to be April 30, 2020. I guess this process started only this year. More examples can be found by simply putting the title from this site to the tiny search box there.
I don't know whether this has been discussed earlier. Why does this happen and what should we do? It seems like an attempt to drive some traffic towards their site. But is this activity allowed?