A lot of PoS coins have forked like this, multiple times (colx, hbn, and many others). I never have red any explanation why this happens, and how to solve it. I cannot believe these numerous forks are attacks alone, there are heavy deficiencies of this implementation. Such coins are useless.
On some PoS coins I never have seen this, decred for example.
dont use this property to promote other coins please
I don't see he is promoting dead coins, instead he was just saying your coin is forked because a known issue, "known" LOL. if dev is unknow of this, that's a pity!