No way to cancel 2-factor auth step

Today I wanted to test a bit of code that required me to be signed out of SSO.
As I imagined I'd be signed in on SSO I fired up a browser and went to login.ubuntu.com to sign out of SSO.
It turns out at the time I was indeed signed in, but my 2-factor auth had expired, so it sent me to https://login.ubuntu.com/two_factor_auth?next=/

At this point I wanted to *log out*, but I had no way to cancel the 2-factor auth login and sign out. The screen has no "Cancel" link, no "I'm somebody else". I ended up logging in just to be able to log out.

I later noticed that if I'd have gone to https://login.ubuntu.com/+logout it would have logged me out, but you need to know this url off by heart.

So, if you use SSO with 2-factor auth and then leave the box unattended and somebody else comes along a while later and tries to use SSO too with their own account, SSO will try ask them to log in with 2-factor auth (which is *great*, as it doesn't allow them to use your account), but it doesn't allow them to log in with their own account either.