Jan 30 17:16:10 localhost sshd: error: Failed to allocate internet-domain X11 display socket.
The solution for me on the server side was the following in sshd_config:
*Remember to restart sshd and also reconnect from the client side.
I had all the normal X11 settings on the server but it just stopped working for me randomly:
I am thinking this is a client side error in the sense that perhaps newer SSH clients cause this bug because things were working fine for months and nothing changed on the server side.
This happened on Linux Mint/Ubuntu/Debian based machines.
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