Bitcoin (BTC-USD) jumped back to over $20K in Friday morning trading as stock index futures implied a higher open opening and the dollar rally stalls somewhat. Over the past 24 hours, the world's largest cryptocurrency by market cap (BTC-USD) soared 9.1% to $20.96K, after hovering at around $19K since the beginning of the week ended September 9. Ethereum (ETH-USD), though not to the same magnitude as BTC, gained 4.9% to $1.71K as of shortly before 9:30 a.m. ET.The intraday upswings pulled up a slew of crypto-related stocks in premarket trading, including Coinbase Global (COIN) +7.7%, Marathon Digital (MARA) +9.1%, MicroStrategy (MSTR) +10%, Riot Blockchain (RIOT) +8.9% and HIVE Blockchain (HIVE) +7.6%. That bullish price action comes as stock index futures perked up, with Dow Futures (INDU) +0.6%, S&P Futures (SPX) +0.7% and Nasdaq Futures (NDX:IND) +0.8%.In the midst of this risk-on day, the U.S. dollar is taking a breather from its historic rally started in July 2021. The U.S. dollar index ("DXY") slid 0.65% to 109.01 but remains up nearly 18% over the past year. Bitcoin (BTC-USD), by comparison, was down almost 55% Y/Y. Since the end of April, bitcoin (BTC-USD) and the nominal broad U.S. Dollar Index have increasingly diverged from each other, as seen in the chart below. Earlier, FTX's Sam Bankman-Fried said told CNBC that the real pain in cryptos is likely over.