The same works with ipinfo.io, it’s what I usually use.

I use and enjoy it too, but sadly it is not FOSS.

That’s a separate OS setting. Signal itself has its own setting for which content is actually sent in the notification.

I don’t use it anymore as I switched to TrueNAS which has the functionality built in, but I used to use docking-station.

https://store.steampowered.com/hwsurvey

All of the results are very odd. If you look through the other categories, Simplified Chinese gained THIRTY percent, the Hard Drive categories also wildly changed, and 32 GB RAM jumped +18%. It seems to me like a bunch of Chinese systems just flooded the statistics.