tmux: Use shell script to complete selfinsert

Use a short shell script to complete the `selfinsert` keytable by
binding all keys that have a mapping in the root table.

.config/tmux/tmux.conf

@@ -97,9 +97,16 @@ bind -T resize 4 selectl main-vertical   \; switchc -T resize
 bind -T resize 5 selectl tiled           \; switchc -T resize
 bind r switchc -T resize
 
-# Allow C-h to still be passed (when programs expect it as backspace, e.g. UEFI
-# shell)
-bind -r -T selfinsert C-h send C-h
+# Create a key-table which self-inserts all keys that are bound in the root key
+# table. (C-h for example is sometimes needed as backspace sequence)
+#
+# tmux_selfinsert.sh:
+#
+# tmux list-keys -T root | awk '{print $4}' | while read key; do
+#   tmux bind -r -T selfinsert "$key" send
+# done
+
+run-shell -b "$XDG_CONFIG_HOME/tmux/tmux_selfinsert.sh"
 bind C-v switchc -T selfinsert
 
 # Synchronize the panes in the current window with `<prefix>S`

.config/tmux/tmux_selfinsert.sh

@@ -0,0 +1,8 @@
+#!/bin/sh
+#
+# Create a key-table which self-inserts all keys that are bound in the root key
+# table. (C-h for example is sometimes needed as backspace sequence)
+
+tmux list-keys -T root | awk '{print $4}' | while read key; do
+	tmux bind -r -T selfinsert "$key" send
+done