had a similar issue with the upgrade to 42, see this thread.
In my case Mullvad VPN and its lockdown mode was the cause. Logging in Mullvad VPN and deactivating the lockdown mode solved my issue.
Tried so many things (SELinux, Iptables etc.) and it was so easy.
Holy shit! You are my savior! I have Mullvad VPN installed but I haven’t configured lockdown mode. Why was it enabled all of a sudden? And why does lockdown mode work when Mullvad is not even launched (on start-up)?!
Yeah, I spent a lot of hours troubleshooting today, only to find out that it was that easy.
Was activated with an update of Mullvad (mistake by the Mullvad maintainers in my opinion). That is how lockdown mode is supposed to work = as long as you are not connected to a Mullvad server, even if application is not running, you are not supposed to have internet access.
Yea, it looks like an issue with the Mullvad package. I assume this problem will affect many other users as well. I hope they find this post. Thx again for the help!
I had the same issue and as the OP I was troubleshooting nftables and iptables until I went mad.
Out of curiosity, how did you find the problem? I am not even running MullvadVPN, I had the app installed though and that was apprently enough to ruin my day.
yes, I had exactly this problem too. this is insane. I never used mullvad and never had issues until I restarted with system updates …really a poor design app who does not even warn me about it. I am also curious how you figure that out. please teach us. I have spent 2 hours in troubleshooting the network and was going mad too.