Comment 17 for bug 96676

by my understanding, xterm is intended to produce F13-F24 for Shift+F1-Shift+F12, F25-F36 for Ctrl+F1-Ctrl+F12, etc.

This is supported by
as well as

If that's true, then xterm does not do what terminfo says; i.e. it does not produce kf25 for ctrl+F1.

Am I incorrect in that understanding?