Ssh Xforwarding works for app but not for help

I'm using Opensuse Leap 15.5 in a Proxmox lxc container to run the gnucash app. I can ssh into the container and, with Xforwarding, I can use the app remotely on my KDE desktop. Great. However, in the Help menu, if I click on either "Tutorial and Concepts Guide" or "Contents", those windows don't open on my KDE desktop but on the container console. Doesn't seem like an app problem but maybe some detail of forwarding or odd behaviour of yelp, the gnome help viewer. Any thoughts, please?