Roku Inc ROKU.O soared 15.8% after it forecast first-quarter revenue above market estimates. By Johann M Cherian Feb 16 (Reuters) - U.S. main stock indexes slipped on Thursday after unexpectedly strong inflation data and a fall in weekly jobless claims fed into fears that the Federal Reserve will keep raising interest rates to tame high prices. However, signs of a sturdy U.S. economy and an acceleration in January consumer prices recently raised concerns among traders that the Fed may not hit pause on its hawkish policies anytime soon, with hopes of rate cuts later this year receding.