I mean, unless somebody is burning browser zero days on random public QR codes I'm not too worried.

Signal is open source, right? Though that wouldn't stop a bugdoor, it might at least make one harder. As you say, I think getting in through the OS itself is much more likely. Signal would put up much more of an ideological fight than Google, I imagine.

There are possible causes from the physiology that arises from poor sleep, but also the fact that when sleep-deprived it’s difficult to live a healthy life – there is more drinking, more obesity, less exercise, more smoking etc – and these may be what causes any possible increased risk.

They've already called out that it's just an association, more work is needed to show if there's actually causality

At least from the folks I've talked to he is not well-liked

This was my first Discworld novel! Highly recommend.

3:31 here!