I have been trying Kite 3.0 since last week. Last Friday I had logged in to Kite (using Chrome) and hibernated my Windows machine by evening. Today (Monday morning) when I resumed the operating system and went to the tab in which Kite was open (I hadn't closed the tab before hibernating), I could use the application without having to log in again (as in all live updates like index tickers and graph for the chosen symbol were alive). Refreshing the page made Kite ask me to log in again.
It was designed like that. A user will not be logged out until the server responds with 403. This forum is dedicated to Kite Connect related queries only. You can write to support for other platform related queries.
