This has happened to me so many times and it's incredibly frustrating. I log into the agent portal, try to respond to a user's ticket by adding a note. When I hit submit, I'm kicked out of the agent portal back to the login screen. I've lost everything I've typed (and no amount of going back will allow me to find the text).
I'm using the latest Google Chrome on Ubuntu 18.04. I also use AdBlock and Ghostery. Have other users with these plugins experienced similar issues?