Shares of Roku Inc. (ROKU) were volatile in trading on Tuesday after the short selling newsletter Citron Research tweeted that the company is a “total joke”. Citron stated that ROKU’s current valuation should be much lower, but did not elaborate as to why. Citron CEO Andrew Left will appear on CNBC on Wednesday to explain his reasoning. Shares of ROKU dropped as low as 44.76 after the tweet, but ultimately settled at 46.43, down only -0.19% for the day. Keep an eye on ROKU today to see if Citron has a good case or not. Either way, expect volatility in the stock.