Same issue for me.
I have made exceptions/allowances to the AMD software in the antivirus and the firewall, as old posts about issues (not this problem specifically) suggest. Still the same issue. RX 5700XT to a Pixel 2XL
UPDATE: Just updated AMD Adrenaline software, and tried again. This time I launced the AMD software first, then steam, then nothing else. Work. When I tried connecting the app again, but with Chrome open, and it gave me the warning message we've been referring to. So it *might* be Chrome related.