<li>Intermittent DNS issues with some names eg duckduckgo.com</li>
> I wonder if (2) is due to ipv6 being preferred over ipv4 for local wifi lans? I noticed I couldn't browse to the local wifi router anymore under grapheneos. Never had a problem before or with a multitude of other devices.
Do you use a VPN? Some VPNs disable LAN access by default. IIRC the free version of Proton VPN doesn't allow you to access LAN while connected at all.