ReForris UI ignores the port that it's running on when opening websocket connections

I remotely access another Turris Omnia router using ssh forwarding via a remote server:

Host remote-server.example
    LocalForward 8443 192.168.1.1:443

which means that in order to access the web UI for that remote Omnia, I go through a server I have access to on that network:

ssh remote-server.example
xdg-open https://localhost:8443/

Unfortunately, that doesn't work and ReForris gets stuck in an infinite redirect loop as soon as I log in:

If I use my local root account and forward the remote port to the local 443 port, then it works fine:

Host remote-server.example
    User normaluser
    LocalForward 443 192.168.1.1:443

I suspect that it's just a matter of hard-coding both the hostname and the port of the resources to load in the UI.