I'm having an issue when I reply to a thread using my android tablet. I'll click the link in gmail, it opens in the gmail app, not chrome. I reply then go to edit what I said, my reply gets deleted as soon as I put my finger on what I want to edit.
Sounds like you have 2 issues. The 1st one, message was too short, you probably typed your reply into a quote box or some how clicked to put a quote box around it. I've had that happen on my cell and tablet.
The token has expired is when I leave WS threads open, I will come back some time later, it will tell me the token has expired, I have to reload the window. What I do there is copy my reply, then go into the thread, right click reply to thread, then paste my reply into a fresh reply box. I get this on my windows vista computer
Are you using a computer when you get the errors?