Same here. The release notes say there was a fix for the “Are you sure you want to exit” dialog, maybe something to do with that fix.

Cockpit is what I use. Simple setup and shows all sorts of graphs and statistics. https://cockpit-project.org/

Those were cool!

Definitely not new. This is how RFID tags work. They harvest energy from the transmitter to power the circuitry in the tag to send back a response.