Fix clipboard copy across terminal emulator -> tmux -> SSH -> tmux -> nvim

bin/clipboard-copy

@@ -0,0 +1,27 @@
+#!/bin/sh
+# Copy stdin to the system clipboard, regardless of platform or how deep in
+# ssh/tmux this shell is: prefer a local clipboard tool for the current
+# display server, and fall back to OSC 52 (wrapped for tmux's DCS
+# passthrough, since tmux's own Ms-based OSC 52 forwarding doesn't reliably
+# reach every terminal) when no local tool is available.
+if command -v pbcopy >/dev/null 2>&1; then
+    exec pbcopy
+elif [ -n "$WAYLAND_DISPLAY" ] && command -v wl-copy >/dev/null 2>&1; then
+    # wl-copy/xclip both hold the selection by staying alive as a background
+    # process (X11/Wayland selections have no central store -- the owner has
+    # to serve paste requests live). setsid -f detaches that process from
+    # our session so tmux's copy-pipe job cleanup can't kill it right after.
+    setsid -f wl-copy
+elif [ -n "$DISPLAY" ] && command -v xclip >/dev/null 2>&1; then
+    setsid -f xclip -selection clipboard
+else
+    # No local clipboard tool -- most likely this is a remote host reached
+    # over ssh, possibly with one or more local tmux hops between here and
+    # the actual display that this process has no way to detect. Send both
+    # the raw form and the tmux-DCS-passthrough-wrapped form: whichever one
+    # the chain in between doesn't understand is silently dropped, and the
+    # other gets through.
+    data=$(base64 | tr -d '\n')
+    printf '\033]52;c;%s\a' "$data" > /dev/tty
+    printf '\033Ptmux;\033\033]52;c;%s\a\033\\' "$data" > /dev/tty
+fi

config/nvim/lua/config/options.lua

@@ -60,18 +60,24 @@ opt.splitright = true
 opt.updatetime = 300
 opt.shortmess:append("c")
 
--- Clipboard: OSC 52 copy-only. This sends the "+ / "* register content to
--- the real terminal via escape sequence, so <leader>y works whether nvim is
--- local or several ssh/tmux hops deep -- no xclip/wl-copy/pbcopy needed on
--- the remote host. Paste is intentionally left as a no-op: OSC 52 read
--- support is inconsistent across terminals and can hang waiting for a
--- reply, so use the terminal's own native paste (e.g. Ctrl-Shift-V) instead.
-local osc52 = require("vim.ui.clipboard.osc52")
+-- Clipboard: copy-only, via dotfiles/bin/clipboard-copy. This is a small
+-- script (rather than nvim's built-in raw-OSC-52-only provider) because
+-- reaching the real clipboard needs more than a raw OSC 52 write: it picks
+-- pbcopy/xclip/wl-copy when nvim is running locally, and when none of those
+-- are available (nvim on a remote host with no local display) sends OSC 52
+-- both raw and wrapped for tmux's DCS passthrough, since it can't know how
+-- many local tmux hops are between it and the real terminal and tmux's own
+-- native OSC 52 forwarding isn't reliable. Works whether nvim is local or
+-- several ssh/tmux hops deep, on any machine sharing this dotfiles repo.
+-- Paste is intentionally left as a no-op: OSC 52 read support is
+-- inconsistent across terminals and can hang waiting for a reply, so use
+-- the terminal's own native paste (e.g. Ctrl-Shift-V) instead.
+local clipboard_copy = vim.fn.expand("~/dotfiles/bin/clipboard-copy")
 vim.g.clipboard = {
-  name = "OSC 52 (copy-only)",
+  name = "clipboard-copy (copy-only)",
   copy = {
-    ["+"] = osc52.copy("+"),
-    ["*"] = osc52.copy("*"),
+    ["+"] = { clipboard_copy },
+    ["*"] = { clipboard_copy },
   },
   paste = {
     ["+"] = function() return {} end,

config/tmux.conf

@@ -49,8 +49,8 @@ bind a setw synchronize-panes
 setw -g mode-keys vi
 set-option -g -q mouse on
 
-bind y run 'tmux save-buffer - | reattach-to-user-namespace pbcopy'
-bind C-y run 'tmux save-buffer - | reattach-to-user-namespace pbcopy'
+bind y run 'tmux save-buffer - | $HOME/dotfiles/bin/clipboard-copy'
+bind C-y run 'tmux save-buffer - | $HOME/dotfiles/bin/clipboard-copy'
 
 # Let OSC 52 escape sequences (e.g. nvim's clipboard writes) pass through
 # this tmux to the real terminal, even when nested behind ssh/tmux layers.
@@ -68,14 +68,23 @@ if-shell "tmux -V | awk '{print $2}' | awk -F. '{if ($1*1000+$2 >= 3003) exit 0;
 if-shell "tmux -V | awk '{print $2}' | awk -F. '{if ($1*1000+$2 >= 3002) exit 0; else exit 1}'" 'set -s extended-keys on; set -as terminal-features "*:extkeys"'
 
 # Also make tmux's own copies (mouse-drag select in copy-mode, prefix-[ y,
-# etc.) reach the real system CLIPBOARD via OSC 52 -- not just PRIMARY/
-# middle-click -- by declaring the "Ms" (set-clipboard) terminfo capability
-# tmux needs to emit the escape sequence itself, then telling tmux to use it.
-# "external" only ever writes; it never asks the terminal to reply, so this
-# can't hang the way an OSC 52 read query can.
+# etc.) reach the real system CLIPBOARD -- not just PRIMARY/middle-click.
+# tmux's built-in mechanism for this is declaring the "Ms" terminfo
+# capability and setting set-clipboard so tmux emits the OSC 52 escape
+# itself, which is what these two lines do. Kept as a harmless attempt for
+# terminals where it works, but confirmed unreliable against Alacritty (both
+# pane-forwarded and tmux-generated OSC 52 silently failed to reach the
+# clipboard even with Ms correctly registered) -- copy-command below is the
+# mechanism actually proven to work here, via bin/clipboard-copy.
 set -as terminal-overrides ',*:Ms=\E]52;c;%p2%s\007'
 set -g set-clipboard external
 
+# The default/no-argument form of copy-pipe (used by double/triple-click and
+# a couple of default bindings) pipes to this option instead of a literal
+# command -- route it through the same working script as the explicit
+# copy-pipe bindings in tmux/modern.conf.
+set -g copy-command '$HOME/dotfiles/bin/clipboard-copy'
+
 # iTerm2 supports SIXEL images (since 3.3.0) but doesn't set a distinct TERM
 # to identify itself, so this matches on its usual "xterm-256color" report --
 # any other client reporting that same TERM will also be treated as

config/tmux/legacy.conf

@@ -7,9 +7,9 @@ bind-key -t vi-copy NPage page-down
 bind-key -t vi-copy WheelUpPane halfpage-up
 bind-key -t vi-copy WheelDownPane halfpage-down
 bind-key -t vi-copy v begin-selection
-bind-key -t vi-copy y copy-pipe "reattach-to-user-namespace pbcopy"
+bind-key -t vi-copy y copy-pipe "$HOME/dotfiles/bin/clipboard-copy"
 unbind-key -t vi-copy Enter
-bind-key -t vi-copy Enter copy-pipe "reattach-to-user-namespace pbcopy"
+bind-key -t vi-copy Enter copy-pipe "$HOME/dotfiles/bin/clipboard-copy"
 
 bind-key -n PPage if-shell -F "#{alternate_on}" "send-keys PPage" "copy-mode -e; send-keys PPage"
 bind-key -n WheelUpPane if-shell -F -t = "#{alternate_on}" "send-keys -M" "select-pane -t =; copy-mode -e; send-keys -M"

config/tmux/modern.conf

@@ -6,9 +6,16 @@ bind-key -T copy-mode-vi NPage send-keys -X page-down
 bind-key -T copy-mode-vi WheelUpPane send-keys -X halfpage-up
 bind-key -T copy-mode-vi WheelDownPane send-keys -X halfpage-down
 bind-key -T copy-mode-vi v send-keys -X begin-selection
-bind-key -T copy-mode-vi y send-keys -X copy-pipe "reattach-to-user-namespace pbcopy"
+bind-key -T copy-mode-vi y send-keys -X copy-pipe "$HOME/dotfiles/bin/clipboard-copy"
 unbind-key -T copy-mode-vi Enter
-bind-key -T copy-mode-vi Enter send-keys -X copy-pipe "reattach-to-user-namespace pbcopy"
+bind-key -T copy-mode-vi Enter send-keys -X copy-pipe "$HOME/dotfiles/bin/clipboard-copy"
+
+# The default MouseDragEnd1Pane binding (copy-selection-and-cancel) relies on
+# tmux's own OSC 52 write via the Ms terminfo capability, which doesn't
+# reliably reach every terminal (confirmed broken against Alacritty here).
+# Route mouse-drag copies through the same clipboard-copy script as keyboard
+# yanks instead, so both use the mechanism that's actually proven to work.
+bind-key -T copy-mode-vi MouseDragEnd1Pane send-keys -X copy-pipe-and-cancel "$HOME/dotfiles/bin/clipboard-copy"
 
 # Let mouse wheel / PageUp pass through to apps using the alternate screen
 # (vim, less, etc.) instead of always entering copy-mode