What games do you have? Most of my games work great with steams proton. Only some multiplayer games with some anticheat are not supported. I think from my ~260 Games +90% are working Check out protondb.com

Only because Ubisoft does have problems. If their finances would be better they would’nt do it. That’s my opinion. I will never trust this company again.

I do have the same error but i installed bnet via steam. Changing the runner to another proton version (official proton and proton-ge) wont change anything. How to change to a wine-ge version in steam? Or is there another fix? I tried a few of the suggested things from the links but nothing worked :( My OS is Mint 22 Cinnamon I do have proton tricks but no winetricks.

No update available (stable) and rebooted multiple times. Sadly no change :(

Its a internet service/company that wants to make HTTPS available for everyone. Because of security reasons. You can create an Lets Encrypt Account, Register your servers DNS in any DNS service out there and then link your server to your Lets Encrypt Account. Then you can get SSL cert for your DNS Record/your server. I think it is valid for 90 days. You can renew the cert when there are 30 days left i think. So its free SSL for your webserver connection. This is a realy basic explanation but i think to understand what it does its enough ;) Hope this helps - If not, feel free to ask more :)

Edit: your webserver must be accessible from the www