Caps Lock no longer types <F22> into Neovim

Caps Lock sends F20, and the terminal passes it on as well as Wispr Flow
seeing it. tmux reads it as S-F10 and hands the pane ESC[21;2~, which Neovim
decodes as <F22> and, with nothing mapped to it, types out as text -- once per
repeat while the key is held.

Dropped in both places, each enough alone: Neovim maps <F20> and <F22> to
nothing, terminal mode included so a :terminal does not pass it to its shell,
and tmux binds S-F10 to an empty command, which also swallows a real
Shift+F10 that nothing here uses. The empty binding loads on tmux 3.5a and 3.4.

From change request cee596.

2 files changed, 19 insertions, 0 deletions

diff --git a/config/nvim/init.lua b/config/nvim/init.lua
index 3f094e8..89ab1b8 100644
--- a/config/nvim/init.lua
+++ b/config/nvim/init.lua
@@ -242,6 +242,19 @@ if not vim.g.lazy_bootstrapped then
 end
 
 ------------------------------------------------------
+---- Caps Lock key -----------------------------------
+------------------------------------------------------
+
+-- Caps Lock sends F20 (hammerspoon), which reaches Neovim as F22 through tmux.
+-- Neovim types the name of a function key nothing maps, so holding it filled
+-- the buffer with <F22>. Wispr Flow reads the key before the terminal does, so
+-- nothing is lost by dropping it here. Terminal mode too, or holding it in a
+-- :terminal would send the key on to the shell running there.
+for _, key in ipairs({ "<F20>", "<F22>" }) do
+	vim.keymap.set({ "n", "x", "s", "o", "i", "c", "t" }, key, "<Nop>")
+end
+
+------------------------------------------------------
 ---- Terminal ----------------------------------------
 ------------------------------------------------------
 
diff --git a/config/tmux.conf b/config/tmux.conf
index 913a968..ceb59e6 100644
--- a/config/tmux.conf
+++ b/config/tmux.conf
@@ -155,6 +155,12 @@ set -g allow-passthrough on
 # See: https://github.com/ghostty-org/ghostty/issues/7997
 set -g extended-keys off
 
+# Caps Lock is F20 (hammerspoon). What reaches tmux for it is read as S-F10 and
+# passed on as ESC[21;2~, which Neovim takes for F22 and types out as text. Wispr
+# Flow reads the key before the terminal does, so nothing here needs it: drop it.
+# This also drops a real Shift+F10.
+bind-key -n S-F10 {}
+
 # Machine-local overrides, where a machine has any: ~/.tmux.conf.local, a real
 # file in no repo, like ~/.localprofile for the shell. Not under ~/.config/tmux,
 # which is a link into this repo. Last, so it wins over everything above,