I am a Kitty user and am able to name a “window”(pane) and then send-keys to it really easily. However, I was thinking of switching to TMUX because of some other functionality and wanted to be able to do the same thing. So, I put in an issue on Github and someone was nice enough to send me a diff.txt file that might provide the functionality (?) Problem is that I don’t know what to do with the file. Here is a link to the Github issues thread:
The diff file nicm (who is the tmux author) attached looks like a git diff file to me, so you would need to have a set up to build tmux from source (see the dependencies in the README and this section). Then you would download the diff file and apply it to the source code in the tmux folder you cloned using git, with the command git apply tmux-find-pane-title.diff.txt. You can then build tmux following the linked instructions and test out if the resulting tmux binary works as you would expect.
Are you using the repl commands that come with Kakoune by default, or something else? They should auto-detect tmux and work with it out of the box. repl/tmux.kak uses the pane id instead of the title, just like the tmux developer suggests.