The stock market graphic of Zillow Group is displayed on a smartphone with the logo of Zillow in the background on Feb. 21, 2021.Zillow shares plunged more than 9% on Monday on worries that the online real estate platform could have a big new competitor: Google Search. Google appears to be running tests on putting real estate sale listings into its search results. Over the weekend, real estate tech strategist Mike DelPrete published mobile phone screenshots of Google Search results showing real estate listi ...