A very weird thing happened in the advent of my Samsung Galaxy S4 getting Android 4.4.2. Whenever I would try to type a URL address into the Chrome address bar, the letters would be repeated. So, I would type "m" and end up getting "mm". Sometimes, I could type "msn" and then I'd get "msnmsn". The letter and phrase repeating never happened anywhere else but in the Chrome address bar. I had thought that it was an issue with autocomplete or predictive text, but that's not the case.
I had two keyboard inputs enabled. Using both the Samsung keyboard input and the Swipe keyboard and having them both using predictive text seems to be the culprit . Turning off the predictive text option on Swipe solved the problem.