Hi,

I have just upgraded from 18.04 on a system that was running fine regarding the wifi. it will be sometime unstable while Android phones were ok, but very usable. The upgrade was done over the wireless connection for example.

However, since upgrading, it is almost useless. I get a few minutes of connection when starting the computer, then the connection goes off, and no way to get it back. I get a notification saying: "connection failed. /n Activation of network connection failed"

as an indication, I have a slightly old desktop running ubuntu. The wifi card is the following as named in the system profiler:
Ralink corp. RT5390R 802.11bgn PCIe Wireless Network Adapter

Any suggestion?