In case this helps…
I just set up a new Electron for the first time in a long time. After spending a frustrating hour or so trying different browsers to get past the spinning logo at the “enter sim” step in the instructions I remembered the post about disabling ad blockers and also remembered that I have PiHole running. I tend to forget that; it’s just so seamless in the background of my network.
Disabling PiHole for five minutes solved the problem. Posted in case it helps someone else down the line.
Keywords: Electron, sim card, setup