Poloniex was once a super active crypto exchange that would have 40k users online at any given time, now only around 5-10k. The trading platform is quite nice imo. Poloniex has 4 trading pairs setup, BTC, ETH, XMR, USDT. Poloniex is a US-based exchange which was recently bought by Circle, a company backed by Goldman Sachs Group. Polo does not actively add coins/tokens, nor do they distribute Bitcoin fork coins to their users, for example, they still have not given Bitcoin Gold to users.
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