DoorDash shares slumped Thursday after the food delivery giant posted earnings that missed estimates and warned its costs would continue to rise. Yuki Iwamura / Bloomberg / Getty Images Close Key Takeaways A food delivery giant came under pressure after it missed quarterly profit estimates and warned investments in new technologies could squeeze profits, while better-than-expected results helped send shares of a cloud-based security company higher. Major U.S. equities indexes dropped Thursday, led by tech s ...