Ambiguous Keys

For historical reasons, most terminals (except for some modern ones like Kitty, iTerm, and foot) send the exact same keycodes for different keys. For example, the <tab> key sends the same code as <c-i>. When Kakoune receives an ambiguous code, it has to decide what key to decode it to:

This key	Decodes as
<c-m>	<ret>
<c-j>	<ret>
<c-i>	<tab>
<c-h>	<backspace>

Therefore, if you map a key from the first column, the mapping will not trigger in the regular terminal UI. Instead, you should map the key from the right-hand column to achieve the same effect.

If you really want to map <c-m> instead of <ret> (because <c-m> has some mnemonic value, for example) you can make Kakoune manually trigger the first-column mappings in addition to the second-column mappings:

hook global normal RawKey <ret>       %{ execute-keys -with-maps <c-m>; execute-keys -with-maps <c-j> }
hook global normal RawKey <tab>       %{ execute-keys -with-maps <c-i> }
hook global normal RawKey <backspace> %{ execute-keys -with-maps <c-h> }

Relevant discussions

• https://github.com/mawww/kakoune/issues/1012
• https://github.com/mawww/kakoune/issues/2209
• https://github.com/mawww/kakoune/issues/2554