If you set up a tunnel using Dynamic forwarding (equivalent of ssh "-D" option) to make a SOCKS5 proxy and then try to use it with Firefox, and you have "Proxy DNS when using SOCKS v5" enabled, OR you have DNS over HTTPS enabled, no web pages will load. So it appears that the Dynamic forwarding option in the tunnel setup is blocking DNS for some reason. This has not been an issue in other terminal software even when connecting to the same site. In addition there is no option I have found to make the connection persistent (that is to say, to make it automatically reconnect if the connection is lost) or in the alternative to use autossh to create the tunnel.