I saw that but, since it worked flawlessy and it does not anymore, I suspect a problem of the same kind (kernel).
And if it is, my current knowledge of linux won’t be sufficient to diagnose and/or troubleshoot further.
Actually, I bought 3 different wifi USB adapters. 8 months ago, when I tried to understand why the other 2 did not work with Qubes (those 2 never worked with Qubes), I found that explanation. If my understanding is correct, this issue #3778 is related to RT2800USB, which is not the atheros wifi adapter, though. (?)
I mean that it worked flawlessy about 2 months ago. I have no idea why it stopped working when I tried again 4 days ago. As far as I remember, I have not modified my disp-sys-usb nor my disposable NetVM.
Alfa AWUS036NHA
Atheros 9271
Actually, I have already bought 3 of them. Perhaps not the good ones, though!!! I had not read #3778 at the time of the purchase. All of them were running on my Raspberry Pi. Hopefully, this is still the case and I will be luckier than with Qubes (where Atheros suddently stopped working). If so, I will connect my Qubes–ethernet cable–>Raspberry Pi–>Atheros USB wifi adaptor (or one of the 2 others). My Raspberry Pi (with IP forwarding) will be kind of an adaptor between my Qubes and my wifi USB adapter.
Certainly not the most convenient but a solution that might work with my current level of knowledge.
Thanks again for your time, researches and ideas. Very much appreciated!!