My sign-in screen (I think that's what it's called) has suddenly stopped appearing and now needs to be summoned with the Ctrl-Alt-Del command (whereas previously I just had to press a key and it would come up automatically).
Is this the sign of an impending systemic failure or is it easily rectified? Or perhaps the result of an upgrade?
Firefox has also recently started freezing - not sure whether the two things are connected.
The laptop (Lenovo) is fairly new, but out of guarantee (of course).