What am I missing here?
If there were only two pilots in the cockpit, then the F/O obviously had been released to line - or at the very least, the TRE had released the safety pilot - and therefore this F/O could be left alone in the cockpit if the Captain needed a pee.
That said, it is the height of stupidity for an F/O so new and inexperienced to behave in this way.
In our airline we have seen cadets texting on their mobiles during SIM training and Line training - I kid you not.
Where has this slack attitude come from? Unlike dinosaurs like me, I suppose that the cadets coming through now are the first generation to have had mobile phones and tablet computers from a very very early age, (I got my first mobile phone aged 35ish), so they probably don't see anything wrong with using one constantly, and the fact that it is highly inappropriate and dangerous probably doesn't even occur to them.
