accessing the host's X server from inside chroot

[Kostas Oikonomou]

I am running FreeBSD 12.0p10.  Using chroot, I am trying to run a browser
(palemoon) located in /opt/devuan, which contains a Devuan Linux distribution
installed with 'debootstrap'.  My objective is for the browser to use the host's
(FreeBSD)
X server, not the Devuan one.

I've added my FreeBSD user name as a Devuan user, home in /opt/devuan/home.  
Now I try things like

sudo chroot -u <me> /opt/devuan home/palemoon/palemoon

but I cannot get past the error

Error: cannot open display: :0.0

Running

sudo chroot -u <me> /opt/devuan home/palemoon/palemoon --help

works, and produces the expected text output.

I've tried things like "xhost +"  and I've searched lots of mailing lists, but I
don't see any answer.

Thanks for your help.