update .tmux.conf with osc52-related additions

.tmux.conf

@@ -63,3 +63,13 @@ bind % split-window -h -c "#{pane_current_path}"
 unbind -T copy-mode-vi MouseDragEnd1Pane
 bind -T copy-mode-vi MouseDragEnd1Pane send -X stop-dragging-selection
 bind -T copy-mode-vi MouseDown1Pane select-pane \; send-keys -X clear-selection
+
+# Lets both tmux *and* applications inside (like nvim) to set the system
+# clipboard. Older versions of tmux had this set to "on" by default, which
+# changed to "external" in v2.6, at which time it blocked apps inside like
+# nvim. So we set it back to "on".
+set -s set-clipboard on
+
+# Only available starting in v3.2. Allows escape sequences, like OSC52, to be
+# passed through which lets us set system clipboard.
+set -g allow-passthrough on

docs/changelog.rst

@@ -1,6 +1,14 @@
 Changelog
 =========
 
+2026-07-27
+----------
+
+**tmux**
+
+Add ``set-clipboard on`` and ``allow-passthrough on`` in :file:`~/.tmux.conf`
+to support OSC52 clipboard behavior within apps (like nvim) inside tmux.
+
 2026-06-26
 ----------