Specifies what keyboard protocol to use depending on the value of 'term'. The supported keyboard protocols names are: none whatever the terminal uses mok2 modifyOtherKeys level 2, as supported by xterm kitty Kitty keyboard protocol, as supported by Kitty

The option value is a list of comma separated items. Each item has a pattern that is matched against the 'term' option, a colon and the protocol name to be used. To illustrate this, the default value would be set with:

set keyprotocol=kitty:kitty,foot:kitty,wezterm:kitty,xterm:mok2

This means that when 'term' contains "kitty, "foot" or "wezterm" somewhere then the "kitty" protocol is used. When 'term' contains "xterm" somewhere, then the "mok2" protocol is used.

The first match is used, thus if you want to have "kitty" use the kitty protocol, but "badkitty" not, then you should match "badkitty" first and use the "none" value:

set keyprotocol=badkitty:none,kitty:kitty

The option is used after 'term' has been changed. First the termcap entries are set, possibly using the builtin list, see builtin-terms. Then this option is inspected and if there is a match and a protocol is specified the following happens: none Nothing, the regular t_TE and t_TI values remain

    mok2    The t_TE value is changed to:
                CSI >4;m    disables modifyOtherKeys
            The t_TI value is changed to:
                CSI >4;2m   enables modifyOtherKeys
                CSI ?4m     request the modifyOtherKeys state

    kitty   The t_TE value is changed to:
                CSI >4;m    disables modifyOtherKeys
                CSI =0;1u   disables the kitty keyboard protocol
            The t_TI value is changed to:
                CSI =1;1u   enables the kitty keyboard protocol
                CSI ?u      request kitty keyboard protocol state
                CSI >c      request the termresponse

If you notice problems, such as characters being displayed that disappear after CTRL-L, you might want to try making this option empty. Then set the 'term' option to have it take effect:

set keyprotocol=
let &term = &term

(default: see below)