

The tube that turned out not to be PTFE is a nasty surprise. On the fan side, if you run Klipper: heater_fan only switches the fan on above a temperature, it can’t tell that the fan is unplugged. A fan with a tachometer wire and tachometer_pin set at least shows you the RPM, and you could add a macro that pauses the print if it reads zero while the hotend is hot.
The low-tech version is to look at the heatsink fan spinning after any toolhead work, before the first heat-up. Cheap habit compared to rebuilding a melted toolhead.


The phone-shop detail is the most alarming part for anyone at risk there: a device compromised before you even switch it on defeats most of the usual advice. For journalists and activists in that position, the practical baseline is buying devices from a large retailer or outside the country rather than a local shop, keeping the OS fully updated, and on iPhone turning on Lockdown Mode, which was built for exactly this kind of targeting.
Amnesty’s Security Lab also maintains the open-source Mobile Verification Toolkit (MVT) for checking phones, and Access Now runs a free digital security helpline for civil society if someone suspects they’ve been targeted.