They added wifi with a extra circuit board hidden inside the calculator case. It’s connected to the calculators communication port, and pretends to be another calculator. So they can use the calculator’s built in “send” function to send variables/text/etc to the hidden card, which then uses it’s internet connection to look up answers and send the results back.
Recently ran into an issue with Endeavour OS where the built in printer program would give errors when trying to add my network ecotank printer.
Tried using cups terminal and it worked the first time, and is still working weeks later.
So some of the GUI printer apps that distros ship with have issues apparently, but I don’t know the extent of it.