Investors double down on tech stocks in massive DoorDash, Airbnb, C3.ai IPOs December 12, 2020 | No Comments 1261 Shares Share on Facebook Share on Twitter Editors note: Get this free weekly recap of TechCrunch news that any startup can use by email every Saturday morning (7 a.m. PT). Subscribe here. Maybe it is a stock market bubble, or a tech-stock b… [+10358 chars] Stock Market for Beginners