On Sat, 2022-06-11 at 19:50 -0600, home user wrote:
Multiple times over 4-5 hours I
- powered down and powered up the modem;
- reset the modem;
- disconnected and reconnected the yellow ethernet cable; and
- rebooted the work station, trying both OSs.
So I switched back and forth multiple times. There also were other URLs that worked in windows-7 but not Fedora-35, but I think 3 URLs were enough of a sample for this thread.
Sounds like your ISP had problems. Do they have a status page? If so, have a look, see if it lists past outages, bookmark it for next time (also find its IP, now, so you can check if DNS doesn't work in the future).