When you make a phone call, the antenna’s are used 100% for calling and using data is disabled (or at least, it used to be). Android might thus “pretend” that it is still connected.

Derp, indeed

Typo: s/FOUR/FOR/

Yeah, but there is no button to remove all of them at once. And the next time you’ll visit the site, they’ll just get installed again - so I don’t think it is very useful to delete them.

This is a browser feature called ‘service workers’ which indeed allows websites to keep a process running for e.g. notifications.and pending updates.

Can be highly annoying. Visit ‘about:serviceworkers‘ to see the installed ones.