Slack revenue growth fails to impress, shares tank

(Reuters) - Slack Technologies Inc on Thursday posted slowing quarterly sales growth, disappointing investors who had expected a surge in demand for its workplace messaging app as companies rapidly adopt remote working tools and technology.Slack also withdrew its 2021 billing outlook citing uncertainty driven by the COVID-19 pandemic, and said it had seen sales from some large customers slow down in the worst-affected industries, such as travel, hospitality and ride-sharing."There's less..