SSH Session Page Up/Down keys don't function correctly

I've just started switching some of my SSH sessions from the legacy PuTTY type, to the new SSH type.

However, I've noticed one thing that isn't working well, and that is sending page up and page down commands to the terminal.

In my inputrc on a Linux server I usually have the following to allow search forward and back of previous commands:

"\e[5~": history-search-backward
"\e[6~": history-search-forward



When I set the terminal session to use ESC[n~ to send function keys (or Linux or Xterm), nothing at all seems to be sent for these keys.

I've checked this by running showkey on the server, and I see nothing sent using the SSH session, but in the PuTTY session, I do see keys sent.

Can we get this functionality looked at?