Logged out while working

I’m writing a post, editing a draft. I look away for 2min and it’s popped up with a login form. It’s happened a few times. Sometimes I lose my work. This time I can’t get in because there’s some broken recaptcha on the form.
Why do you need this? I’m working, you don’t need to log me out. It’s annoying at least, with 5-9 windows open I have to do this in each one, when it worked.
With my broken recaptcha I’m losing al my work.