Not with -X (untrusted). Not with -Y (trusted). Can’t generate a .Xauthority. Followed the instructions of https://docs.01.org/clearlinux/latest/guides/network/openssh-server.html and tried just about every suggestion I could find with Google–too many to report in detail.
Fedora (usually a pain because of security) and Ubuntu work right out of the box.
Our security policies here are the reason this does NOT work by default. This was a deliberate choice we made.
Read man stateless - it shows the exact changes needed to enable X11 forwarding properly in clearlinux.
I’ve opened OpenSSH X11 instructions need to be upated · Issue #1027 · clearlinux/clear-linux-documentation · GitHub to get the website documentation updated.
FWIW, this is now neatly documented here.