diff --git a/regress/choose-tree.sh b/regress/choose-tree.sh
index 132890730..4656963e6 100644
--- a/regress/choose-tree.sh
+++ b/regress/choose-tree.sh
@@ -290,4 +290,92 @@ wait_count ': G4' 7
 	fail "window 1 of zzz not killed"
 exit_mode q
 
+# --- help and information preview --------------------------------------------
+# The complete tree help is taller than the 24-line test terminal, where the
+# help renderer deliberately leaves the tree unchanged.
+$TMUX2 resize-window -t out:0 -x 80 -y 50 || exit 1
+i=0
+while [ "$i" -lt 50 ]; do
+	# The inner session has a one-line status, leaving a 49-line window.
+	[ "$($TMUX display-message -p -t aaa:0 '#{window_height}')" -ge 49 ] &&
+		break
+	sleep 0.2
+	i=$((i + 1))
+done
+[ "$i" -lt 50 ] || fail "attached client did not resize for tree help"
+$TMUX choose-tree -t aaa:0 -F 'G5' -O index || exit 1
+wait_count ': G5' 7
+$TMUX2 send-keys -t out:0 F1 || fail "send-keys F1 failed"
+wait_for 'Swap current and previous window'
+# The first key closes help; the second exits the tree.
+$TMUX send-keys -t aaa:0 q q || fail "send-keys help exit failed"
+wait_mode aaa:0 0
+
+$TMUX choose-tree -t aaa:0 -F 'G6' -O index || exit 1
+wait_count ': G6' 7
+$TMUX send-keys -t aaa:0 i || fail "send-keys info failed"
+wait_for 'Session'
+$TMUX send-keys -t aaa:0 i || fail "send-keys preview failed"
+exit_mode q
+
+# --- window swapping and command prompt for current/tagged items -------------
+# Restrict a window-only tree to two disposable windows in aaa. J (the
+# Shift-Down equivalent) swaps their window objects while leaving their indexes
+# in place.
+$TMUX new-window -d -t aaa: -n swap-a 'cat' || exit 1
+$TMUX new-window -d -t aaa: -n swap-b 'cat' || exit 1
+aidx=$($TMUX list-windows -t aaa -F '#{window_index}:#{window_name}' | \
+    awk -F: '$2 == "swap-a" {print $1}')
+bidx=$($TMUX list-windows -t aaa -F '#{window_index}:#{window_name}' | \
+    awk -F: '$2 == "swap-b" {print $1}')
+$TMUX choose-tree -w -t aaa:0 -O index -F 'WT #{window_name}' \
+	-f '#{m:swap-*,#{window_name}}' || exit 1
+wait_count 'WT swap-' 2
+$TMUX send-keys -t aaa:0 g j J || fail "window tree swap failed"
+i=0
+while [ "$i" -lt 50 ]; do
+	aname=$($TMUX display-message -p -t "aaa:$aidx" '#{window_name}')
+	bname=$($TMUX display-message -p -t "aaa:$bidx" '#{window_name}')
+	[ "$aname:$bname" = 'swap-b:swap-a' ] && break
+	sleep 0.2
+	i=$((i + 1))
+done
+[ "$i" -lt 50 ] || fail "window tree did not swap the two windows"
+
+# ':' runs an entered command for the current item and rebuilds the tree when
+# its queued command completes.
+$TMUX set-option -g @tree-command '' || exit 1
+$TMUX send-keys -t aaa:0 : || fail "window tree command prompt failed"
+wait_for '(current)'
+$TMUX send-keys -t aaa:0 -l "set-option -g @tree-command '%%'" || exit 1
+$TMUX send-keys -t aaa:0 Enter || exit 1
+i=0
+while [ "$i" -lt 50 ]; do
+	value=$($TMUX show-option -gqv @tree-command)
+	[ -n "$value" ] && break
+	sleep 0.2
+	i=$((i + 1))
+done
+[ "$i" -lt 50 ] || fail "window tree entered command did not run"
+case "$value" in
+=aaa:*.) ;;
+*) fail "window tree command target was '$value'" ;;
+esac
+
+# Tag both disposable windows and kill them through the tagged confirmation
+# callback. The mode-hosting window is outside the filter and survives.
+$TMUX send-keys -t aaa:0 g j t j t X || fail "tagged kill keys failed"
+wait_for 'Kill 2 tagged?'
+$TMUX send-keys -t aaa:0 y || fail "tagged kill confirmation failed"
+i=0
+while [ "$i" -lt 50 ]; do
+	left=$($TMUX list-windows -t aaa -F '#{window_name}' | \
+	    grep -c '^swap-' || true)
+	[ "$left" -eq 0 ] && break
+	sleep 0.2
+	i=$((i + 1))
+done
+[ "$i" -lt 50 ] || fail "tagged windows were not killed"
+exit_mode q
+
 exit 0
diff --git a/regress/clock-mode.sh b/regress/clock-mode.sh
new file mode 100644
index 000000000..846e8dc7e
--- /dev/null
+++ b/regress/clock-mode.sh
@@ -0,0 +1,101 @@
+#!/bin/sh
+
+# Exercise clock-mode initialization, all four styles, its one-second timer,
+# resize into the compact renderer, arbitrary-key exit, and cleanup.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+DIR=$(mktemp -d) || exit 1
+TMUX_TMPDIR=$DIR
+export TMUX_TMPDIR
+INNER="$TEST_TMUX -LtestI$$ -f/dev/null"
+OUTER="$TEST_TMUX -LtestO$$ -f/dev/null"
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+capture()
+{
+	$OUTER capture-pane -p -t outer:0.0 2>/dev/null
+}
+
+wait_mode()
+{
+	want=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		got=$($INNER display-message -p -t clock:0 '#{pane_mode}' 2>/dev/null)
+		[ "$got" = "$want" ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "pane mode is '$got', expected '$want'"
+}
+
+wait_hashes()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		captured=$(capture)
+		printf '%s\n' "$captured" | grep -q '#' && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "large clock did not render"
+}
+
+$INNER new-session -d -s clock -x80 -y24 'exec sleep 100' || exit 1
+$INNER set-option -g status off || exit 1
+$INNER set-option -g window-size manual || exit 1
+$INNER set-option -w clock-mode-colour red || exit 1
+$OUTER new-session -d -s outer -x80 -y24 "$INNER attach -t clock" || exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+sleep 1
+
+for style in 12 24 12-with-seconds 24-with-seconds; do
+	$INNER set-option -w -t clock:0 clock-mode-style "$style" || exit 1
+	$INNER clock-mode -t clock:0 || exit 1
+	wait_mode clock-mode
+	wait_hashes
+	# Let at least one timer callback observe a new second.
+	[ "$style" != 12-with-seconds ] || sleep 1.2
+	$INNER send-keys -t clock:0 x || exit 1
+	wait_mode ''
+done
+
+# Resizing an active mode below the large-glyph threshold selects the compact
+# renderer. A visible time contains a colon and no block-clock hash.
+$INNER clock-mode -t clock:0 || exit 1
+wait_mode clock-mode
+$INNER resize-window -t clock:0 -x20 -y5 || exit 1
+i=0
+while [ "$i" -lt 50 ]; do
+	captured=$(capture)
+	printf '%s\n' "$captured" | grep -Eq '[0-9][0-9]?:[0-9][0-9]' && break
+	sleep 0.1
+	i=$((i + 1))
+done
+[ "$i" -lt 50 ] || fail "compact clock did not render after resize"
+printf '%s\n' "$captured" | grep -q '#' &&
+	fail "compact clock still used large glyphs"
+$INNER send-keys -t clock:0 Enter || exit 1
+wait_mode ''
+
+$INNER has-session -t clock || fail "server died during clock-mode tests"
+exit 0
diff --git a/regress/confirm-before-lock.sh b/regress/confirm-before-lock.sh
new file mode 100644
index 000000000..db570ab10
--- /dev/null
+++ b/regress/confirm-before-lock.sh
@@ -0,0 +1,150 @@
+#!/bin/sh
+
+# Exercise confirm-before's waiting and background callbacks, custom keys and
+# prompts, default-yes handling and errors. Also cover all three lock command
+# entry points with a harmless lock-command which leaves a marker.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+DIR=$(mktemp -d) || exit 1
+TMUX_TMPDIR=$DIR
+export TMUX_TMPDIR
+INNER="$TEST_TMUX -LtestI$$ -f/dev/null"
+OUTER="$TEST_TMUX -LtestO$$ -f/dev/null"
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+capture()
+{
+	$OUTER capture-pane -p -t outer:0.0 2>/dev/null
+}
+
+wait_capture()
+{
+	marker=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		captured=$(capture)
+		printf '%s\n' "$captured" | grep -Fq "$marker" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "timed out waiting for '$marker'"
+}
+
+wait_option()
+{
+	want=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		got=$($INNER show-option -gqv @confirmed 2>/dev/null)
+		[ "$got" = "$want" ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "@confirmed is '$got', expected '$want'"
+}
+
+wait_file()
+{
+	marker=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		[ -f "$marker" ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "lock command did not create $marker"
+}
+
+$INNER new-session -d -s test -x80 -y24 'exec sleep 100' || exit 1
+$INNER set-option -g status on || exit 1
+$INNER set-option -g status-position bottom || exit 1
+$INNER set-option -g window-size manual || exit 1
+$OUTER new-session -d -s outer -x80 -y24 "$INNER attach -t test" || exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+sleep 1
+
+client=$($INNER list-clients -F '#{client_name}')
+[ -n "$client" ] || fail "inner client did not attach"
+
+$INNER bind-key -n M-a confirm-before \
+	'set-option -g @confirmed accepted' || exit 1
+$INNER bind-key -n M-b confirm-before -b -p 'Background?' \
+	'set-option -g @confirmed background' || exit 1
+$INNER bind-key -n M-c confirm-before -c x -p 'Custom?' \
+	'set-option -g @confirmed custom' || exit 1
+$INNER bind-key -n M-y confirm-before -y -p 'Default?' \
+	'set-option -g @confirmed default' || exit 1
+
+# A non-confirming response closes the waiting prompt without running its
+# command; reopening and accepting inserts the command after the waiting item.
+$INNER set-option -g @confirmed sentinel || exit 1
+$OUTER send-keys M-a || exit 1
+wait_capture "Confirm 'set-option'? (y/n)"
+$OUTER send-keys n || exit 1
+sleep 0.2
+wait_option sentinel
+$OUTER send-keys M-a || exit 1
+wait_capture "Confirm 'set-option'? (y/n)"
+$OUTER send-keys y || exit 1
+wait_option accepted
+
+# -b has no waiting queue item and appends its command to the client queue.
+$OUTER send-keys M-b || exit 1
+wait_capture 'Background?'
+$OUTER send-keys y || exit 1
+wait_option background
+
+# A custom printable key is accepted, and -y makes Enter affirmative.
+$OUTER send-keys M-c || exit 1
+wait_capture 'Custom?'
+$OUTER send-keys x || exit 1
+wait_option custom
+$OUTER send-keys M-y || exit 1
+wait_capture 'Default?'
+$OUTER send-keys Enter || exit 1
+wait_option default
+
+# Reject invalid multi-character and control confirmation keys.
+if $INNER confirm-before -b -t "$client" -c xx 'display-message x' \
+    >/dev/null 2>&1; then
+	fail "multi-character confirm key was accepted"
+fi
+if $INNER confirm-before -b -t "$client" -c "$(printf '\001')" \
+    'display-message x' >/dev/null 2>&1; then
+	fail "control confirm key was accepted"
+fi
+
+# lock-client, lock-session and lock-server all send lock-command to the real
+# attached client. The command returns immediately and unlocks the client.
+for kind in client session server; do
+	marker="$DIR/locked-$kind"
+	$INNER set-option -t test lock-command "printf locked >$marker" || exit 1
+	case "$kind" in
+	client) $INNER lock-client -t "$client" || exit 1 ;;
+	session) $INNER lock-session -t test || exit 1 ;;
+	server) $INNER lock-server || exit 1 ;;
+	esac
+	wait_file "$marker"
+done
+
+$INNER has-session -t test || fail "server died during prompt or lock tests"
+exit 0
diff --git a/regress/copy-mode-commands.sh b/regress/copy-mode-commands.sh
new file mode 100644
index 000000000..aa94e9ef2
--- /dev/null
+++ b/regress/copy-mode-commands.sh
@@ -0,0 +1,253 @@
+#!/bin/sh
+
+# Exercise the broad non-mouse copy-mode command surface: navigation, search,
+# jumps, state toggles, line/end-of-line copies, append, and pipe variants.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+DIR=$(mktemp -d) || exit 1
+TMUX_TMPDIR=$DIR
+export TMUX_TMPDIR
+TMUX="$TEST_TMUX -Ltest$$ -f/dev/null"
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$TMUX kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+x()
+{
+	$TMUX send-keys -t copy:0 -X "$@" || fail "copy command failed: $*"
+}
+
+wait_mode()
+{
+	want=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		got=$($TMUX display-message -p -t copy:0 '#{pane_in_mode}' 2>/dev/null)
+		[ "$got" = "$want" ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "pane_in_mode is '$got', expected '$want'"
+}
+
+fresh()
+{
+	$TMUX copy-mode -t copy:0 || exit 1
+	wait_mode 1
+	x history-top
+	x start-of-line
+}
+
+select_text()
+{
+	fresh
+	x begin-selection
+	x cursor-right
+	x cursor-right
+}
+
+$TMUX new-session -d -s copy -x40 -y8 \
+    "sh -c 'i=0; while [ \$i -lt 40 ]; do printf \"  line-%02d needle (a[b]c) end\\n\" \$i; i=\$((i + 1)); done; printf \"\\nparagraph two needle\\n\\nparagraph three\\n\"; printf \"\\033]133;A\\007prompt-one\\n\\033]133;C\\007output-one\\n\\033]133;A\\007prompt-two\\n\\033]133;C\\007output-two\\n\"; exec sleep 100'" ||
+	exit 1
+$TMUX set-option -g status off || exit 1
+$TMUX set-option -g history-limit 200 || exit 1
+
+i=0
+while [ "$i" -lt 50 ]; do
+	history=$($TMUX display-message -p -t copy:0 '#{history_size}')
+	[ "$history" -ge 30 ] && break
+	sleep 0.1
+	i=$((i + 1))
+done
+[ "$i" -lt 50 ] || fail "history did not fill"
+
+fresh
+
+# Copy-mode-specific format callbacks expose the word, line, hyperlink and
+# active search match at the cursor.
+formats=$($TMUX display-message -p -t copy:0 \
+    '#{copy_cursor_word}|#{copy_cursor_line}|#{copy_cursor_hyperlink}|#{search_match}') ||
+	exit 1
+[ -n "$formats" ] || fail "copy-mode cursor formats were empty"
+
+# Cursor, viewport and paragraph commands. Each is asserted by successful
+# dispatch and the final mode-liveness check; detailed word/selection geometry
+# is covered by the existing copy-mode tests.
+for command in back-to-indentation bottom-line top-line middle-line \
+    cursor-centre-vertical cursor-centre-horizontal end-of-line history-bottom \
+    history-top halfpage-down halfpage-up page-down page-up next-paragraph \
+    previous-paragraph next-matching-bracket previous-matching-bracket; do
+	x "$command"
+done
+x goto-line 15
+x set-mark
+x cursor-down
+x jump-to-mark
+
+# OSC 133 prompt and output markers support shell-integration navigation.
+x history-top
+x next-prompt
+case "$($TMUX display-message -p -t copy:0 '#{copy_cursor_line}')" in
+*prompt-one*) ;;
+*) fail "next-prompt did not find prompt-one" ;;
+esac
+x next-prompt
+x previous-prompt
+case "$($TMUX display-message -p -t copy:0 '#{copy_cursor_line}')" in
+*prompt-one*) ;;
+*) fail "previous-prompt did not return to prompt-one" ;;
+esac
+x next-prompt -o
+case "$($TMUX display-message -p -t copy:0 '#{copy_cursor_line}')" in
+*output-one*) ;;
+*) fail "next-prompt -o did not find output-one" ;;
+esac
+
+# Character jumps remember their direction and character for repeat/reverse.
+x jump-forward e
+x jump-again
+x jump-reverse
+x jump-backward e
+x jump-to-forward e
+x jump-to-backward e
+
+# Direct, text and incremental searches cover both directions and the saved
+# search used by again/reverse.
+x search-forward needle
+x search-again
+x search-reverse
+x search-backward needle
+x search-forward-text needle
+x search-backward-text needle
+x search-forward-incremental '=needle'
+x search-forward-incremental '+needle'
+x search-backward-incremental '=needle'
+x search-backward-incremental '-needle'
+
+# Stateful display and behaviour toggles.
+for command in rectangle-on rectangle-off rectangle-toggle \
+    line-numbers-on line-numbers-off line-numbers-toggle \
+    refresh-on refresh-now refresh-off refresh-toggle \
+    scroll-exit-on scroll-exit-off scroll-exit-toggle toggle-position; do
+	x "$command"
+done
+wait_mode 1
+x cancel
+wait_mode 0
+
+# Line and end-of-line copy commands work without an explicit selection.
+fresh
+x select-line
+x copy-selection-and-cancel
+case "$($TMUX show-buffer)" in
+*line-00*) ;;
+*) fail "select-line did not select the current line" ;;
+esac
+
+fresh
+x copy-line
+[ -n "$($TMUX show-buffer)" ] || fail "copy-line produced an empty buffer"
+x cancel
+
+fresh
+x copy-end-of-line
+[ -n "$($TMUX show-buffer)" ] || fail "copy-end-of-line produced an empty buffer"
+x cancel
+
+# Append variants retain or close the mode as advertised.
+$TMUX set-buffer -b append-buffer prefix || exit 1
+select_text
+x append-selection
+appended=$($TMUX show-buffer -b append-buffer)
+case "$appended" in
+prefix*) ;;
+*) fail "append-selection produced '$appended'" ;;
+esac
+x cancel
+
+$TMUX set-buffer -b append-cancel-buffer prefix || exit 1
+select_text
+x append-selection-and-cancel
+wait_mode 0
+appended=$($TMUX show-buffer -b append-cancel-buffer)
+case "$appended" in
+prefix*) ;;
+*) fail "append-selection-and-cancel produced '$appended'" ;;
+esac
+
+# The explicit cancel variants close copy mode.
+fresh
+x copy-line-and-cancel
+wait_mode 0
+fresh
+x copy-end-of-line-and-cancel
+wait_mode 0
+select_text
+x copy-selection-and-cancel
+wait_mode 0
+
+# Pipe wrappers have distinct command handlers. /dev/null keeps the test
+# deterministic while exercising asynchronous pipe job creation and cleanup.
+fresh
+x copy-pipe-line 'cat >/dev/null'
+x cancel
+fresh
+x copy-pipe-line-and-cancel 'cat >/dev/null'
+wait_mode 0
+fresh
+x copy-pipe-end-of-line 'cat >/dev/null'
+x cancel
+fresh
+x copy-pipe-end-of-line-and-cancel 'cat >/dev/null'
+wait_mode 0
+
+select_text
+x copy-pipe-no-clear 'cat >/dev/null'
+x pipe-no-clear 'cat >/dev/null'
+x copy-pipe 'cat >/dev/null'
+x pipe 'cat >/dev/null'
+x cancel
+select_text
+x copy-pipe-and-cancel 'cat >/dev/null'
+wait_mode 0
+select_text
+x pipe-and-cancel 'cat >/dev/null'
+wait_mode 0
+
+# Commands which cancel on downward movement have separate handlers.
+fresh
+x history-bottom
+x bottom-line
+x cursor-down-and-cancel
+wait_mode 0
+fresh
+x history-bottom
+x halfpage-down-and-cancel
+wait_mode 0
+fresh
+x history-bottom
+x page-down-and-cancel
+wait_mode 0
+fresh
+x history-bottom
+x bottom-line
+x scroll-down-and-cancel
+wait_mode 0
+
+$TMUX has-session -t copy || fail "server died during copy-mode commands"
+exit 0
diff --git a/regress/find-window.sh b/regress/find-window.sh
new file mode 100644
index 000000000..820a4777d
--- /dev/null
+++ b/regress/find-window.sh
@@ -0,0 +1,118 @@
+#!/bin/sh
+
+# Exercise find-window's content, name and title filters in every combination,
+# glob/regex and case-insensitive suffixes, plus zoom restoration.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+DIR=$(mktemp -d) || exit 1
+TMUX_TMPDIR=$DIR
+export TMUX_TMPDIR
+INNER="$TEST_TMUX -LtestI$$ -f/dev/null"
+OUTER="$TEST_TMUX -LtestO$$ -f/dev/null"
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+capture()
+{
+	$OUTER capture-pane -p -t outer:0.0 2>/dev/null
+}
+
+wait_mode()
+{
+	want=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		got=$($INNER display-message -p -t find:base.0 '#{pane_mode}' 2>/dev/null)
+		[ "$got" = "$want" ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "pane mode is '$got', expected '$want'"
+}
+
+run_find()
+{
+	label=$1
+	expected=$2
+	shift 2
+	$INNER find-window -t find:base.0 "$@" || fail "$label failed"
+	wait_mode tree-mode
+	i=0
+	while [ "$i" -lt 50 ]; do
+		captured=$(capture)
+		printf '%s\n' "$captured" | grep -Fq "$expected" && break
+		sleep 0.1
+		i=$((i + 1))
+	done
+	[ "$i" -lt 50 ] || fail "$label did not show '$expected'"
+	$INNER send-keys -t find:base.0 q || exit 1
+	wait_mode ''
+}
+
+$INNER new-session -d -s find -n base -x80 -y24 \
+	"sh -c 'printf \"BaseBody\\n\"; exec sleep 100'" || exit 1
+$INNER split-window -d -h -t find:base \
+	"sh -c 'printf \"OtherBody\\n\"; exec sleep 100'" || exit 1
+$INNER new-window -d -t find: -n NameNeedle 'exec sleep 100' || exit 1
+$INNER new-window -d -t find: -n body \
+	"sh -c 'printf \"BodyNeedle\\n\"; exec sleep 100'" || exit 1
+$INNER new-window -d -t find: -n titled 'exec sleep 100' || exit 1
+$INNER select-pane -t find:titled.0 -T TitleNeedle || exit 1
+$INNER set-option -g status off || exit 1
+$INNER set-option -g window-size manual || exit 1
+$OUTER new-session -d -s outer -x80 -y24 "$INNER attach -t find:base" || exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+sleep 1
+
+# Wait until the body text is in the pane history before searching it.
+i=0
+while [ "$i" -lt 50 ]; do
+	$INNER capture-pane -p -t find:body.0 | grep -Fq BodyNeedle && break
+	sleep 0.1
+	i=$((i + 1))
+done
+[ "$i" -lt 50 ] || fail "pane content was not ready"
+
+# No flags means C+N+T. Then cover all three pairs and all three singletons.
+run_find default NameNeedle NameNeedle
+run_find content-name NameNeedle -C -N NameNeedle
+run_find content-title titled -C -T TitleNeedle
+run_find name-title titled -N -T TitleNeedle
+run_find content-only body -C BodyNeedle
+run_find name-only NameNeedle -N NameNeedle
+run_find title-only titled -T TitleNeedle
+
+# Glob case folding and all regular-expression suffix variants.
+run_find insensitive NameNeedle -N -i nameneedle
+run_find regex NameNeedle -N -r '^NameNeedle$'
+run_find regex-insensitive NameNeedle -N -r -i '^nameneedle$'
+
+# -Z temporarily zooms the target window and restores its prior state on exit.
+$INNER find-window -Z -t find:base.0 -N NameNeedle || exit 1
+wait_mode tree-mode
+[ "$($INNER display-message -p -t find:base '#{window_zoomed_flag}')" = 1 ] ||
+	fail "find-window -Z did not zoom"
+$INNER send-keys -t find:base.0 q || exit 1
+wait_mode ''
+[ "$($INNER display-message -p -t find:base '#{window_zoomed_flag}')" = 0 ] ||
+	fail "find-window -Z did not restore zoom"
+
+exit 0
diff --git a/regress/layout-set.sh b/regress/layout-set.sh
new file mode 100644
index 000000000..ea02195a9
--- /dev/null
+++ b/regress/layout-set.sh
@@ -0,0 +1,126 @@
+#!/bin/sh
+
+# Exercise every predefined layout, next/previous cycling, lookup and restore
+# paths, one-pane early returns, minimum-size handling and floating panes.
+
+PATH=/bin:/usr/bin
+TERM=screen
+export PATH TERM
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+DIR=$(mktemp -d) || exit 1
+TMUX_TMPDIR=$DIR
+export TMUX_TMPDIR
+TMUX="$TEST_TMUX -Ltest$$ -f/dev/null"
+SEEN="$DIR/layouts"
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$TMUX kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+layout()
+{
+	$TMUX display-message -p -t layouts:many '#{window_layout}'
+}
+
+check_layout()
+{
+	name=$1
+	$TMUX select-layout -t layouts:many "$name" ||
+		fail "select-layout $name failed"
+	value=$(layout)
+	[ -n "$value" ] || fail "$name produced an empty layout"
+	if grep -Fxq "$value" "$SEEN"; then
+		fail "$name produced the same layout as an earlier preset"
+	fi
+	printf '%s\n' "$value" >>"$SEEN"
+	[ "$($TMUX list-panes -t layouts:many -F x | wc -l)" -eq 5 ] ||
+		fail "$name lost a pane"
+	[ "$($TMUX list-panes -t layouts:many -F '#{pane_floating_flag}' | \
+	    grep -c '^1$')" -eq 1 ] || fail "$name did not preserve the floating pane"
+}
+
+$TMUX new-session -d -s layouts -n many -x100 -y40 'exec sleep 100' || exit 1
+$TMUX set-option -g window-size manual || exit 1
+$TMUX split-window -d -h -t layouts:many 'exec sleep 100' || exit 1
+$TMUX split-window -d -v -t layouts:many 'exec sleep 100' || exit 1
+$TMUX split-window -d -h -t layouts:many 'exec sleep 100' || exit 1
+floating=$($TMUX new-pane -dP -F '#{pane_id}' -t layouts:many \
+    -x20 -y8 -X10 -Y5 'exec sleep 100') || exit 1
+: >"$SEEN"
+
+# Options exercise percentage and explicit secondary-size calculations.
+$TMUX set-option -w -t layouts:many main-pane-height 30% || exit 1
+$TMUX set-option -w -t layouts:many other-pane-height 12 || exit 1
+$TMUX set-option -w -t layouts:many main-pane-width 35% || exit 1
+$TMUX set-option -w -t layouts:many other-pane-width 20 || exit 1
+
+for name in even-horizontal even-vertical main-horizontal \
+    main-horizontal-mirrored main-vertical main-vertical-mirrored tiled; do
+	check_layout "$name"
+done
+
+# Exact and unique-prefix lookup work; ambiguous and invalid names fail.
+$TMUX select-layout -t layouts:many even-h || fail "unique layout prefix failed"
+$TMUX select-layout -t layouts:many main >/dev/null 2>&1 &&
+	fail "ambiguous layout prefix succeeded"
+$TMUX select-layout -t layouts:many no-such-layout >/dev/null 2>&1 &&
+	fail "invalid layout name succeeded"
+
+# Cycle through all layouts in both directions, including wraparound. The
+# aliases and select-layout flags share layout_set_next/previous.
+first=$(layout)
+i=0
+while [ "$i" -lt 7 ]; do
+	$TMUX next-layout -t layouts:many || exit 1
+	i=$((i + 1))
+done
+[ "$(layout)" = "$first" ] || fail "next-layout did not wrap"
+i=0
+while [ "$i" -lt 7 ]; do
+	$TMUX previous-layout -t layouts:many || exit 1
+	i=$((i + 1))
+done
+[ "$(layout)" = "$first" ] || fail "previous-layout did not wrap"
+$TMUX select-layout -t layouts:many -n || exit 1
+$TMUX select-layout -t layouts:many -p || exit 1
+
+# No argument reapplies the last preset; -o restores the previous layout; -E
+# spreads the current cell without changing the pane set.
+$TMUX kill-pane -t "$floating" || exit 1
+$TMUX select-layout -t layouts:many tiled || exit 1
+tiled=$(layout)
+$TMUX select-layout -t layouts:many even-horizontal || exit 1
+$TMUX select-layout -t layouts:many -o || exit 1
+[ "$(layout)" = "$tiled" ] || fail "select-layout -o did not restore layout"
+$TMUX select-layout -t layouts:many || exit 1
+$TMUX select-layout -t layouts:many -E || exit 1
+
+# Each arranger has a deliberate one-pane early return.
+$TMUX new-window -d -t layouts: -n one 'exec sleep 100' || exit 1
+one=$($TMUX display-message -p -t layouts:one '#{window_layout}')
+for name in even-horizontal even-vertical main-horizontal \
+    main-horizontal-mirrored main-vertical main-vertical-mirrored tiled; do
+	$TMUX select-layout -t layouts:one "$name" || exit 1
+	[ "$($TMUX display-message -p -t layouts:one '#{window_layout}')" = "$one" ] ||
+		fail "$name changed a one-pane layout"
+done
+
+# Force the minimum-size paths without requiring a terminal client.
+$TMUX resize-window -t layouts:many -x10 -y6 || exit 1
+for name in even-horizontal even-vertical main-horizontal \
+    main-horizontal-mirrored main-vertical main-vertical-mirrored tiled; do
+	$TMUX select-layout -t layouts:many "$name" || exit 1
+done
+
+$TMUX has-session -t layouts || fail "server died during layout tests"
+exit 0
diff --git a/regress/list-commands.sh b/regress/list-commands.sh
new file mode 100644
index 000000000..9e1463bea
--- /dev/null
+++ b/regress/list-commands.sh
@@ -0,0 +1,46 @@
+#!/bin/sh
+
+# Exercise list-commands for the full table, a single command, aliases, custom
+# and empty formats, and lookup errors.
+
+PATH=/bin:/usr/bin
+TERM=screen
+export PATH TERM
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+DIR=$(mktemp -d) || exit 1
+TMUX_TMPDIR=$DIR
+export TMUX_TMPDIR
+TMUX="$TEST_TMUX -Ltest$$ -f/dev/null"
+
+cleanup()
+{
+	$TMUX kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+# Keep a server alive across commands. Otherwise a STARTSERVER-only command
+# may exit between invocations and leave a short socket-cleanup race.
+$TMUX new-session -d -s list-commands 'exec sleep 100' || exit 1
+
+all=$($TMUX list-commands) || exit 1
+printf '%s\n' "$all" | grep -q '^attach-session (attach)' || exit 1
+printf '%s\n' "$all" | grep -q '^list-commands (lscm)' || exit 1
+
+one=$($TMUX list-commands -F \
+    '#{command_list_name}|#{command_list_alias}|#{command_list_usage}' \
+    list-commands) || exit 1
+case "$one" in
+'list-commands|lscm|'*) ;;
+*) exit 1 ;;
+esac
+
+# Aliases resolve to their command, while an empty expansion prints no line.
+[ "$($TMUX list-commands -F '#{command_list_name}' lscm)" = list-commands ] ||
+	exit 1
+[ -z "$($TMUX list-commands -F '' list-commands)" ] || exit 1
+
+$TMUX list-commands tmux-no-command-$$ >/dev/null 2>&1 && exit 1
+$TMUX list-commands list >/dev/null 2>&1 && exit 1
+exit 0
diff --git a/regress/prompt-words-history.sh b/regress/prompt-words-history.sh
new file mode 100644
index 000000000..6aaa5689c
--- /dev/null
+++ b/regress/prompt-words-history.sh
@@ -0,0 +1,165 @@
+#!/bin/sh
+
+# Cover prompt word movement in emacs and vi modes, ambiguous inline command
+# completion, and the show/clear-prompt-history command surface.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+DIR=$(mktemp -d) || exit 1
+TMUX_TMPDIR=$DIR
+export TMUX_TMPDIR
+INNER="$TEST_TMUX -LtestI$$ -f/dev/null"
+OUTER="$TEST_TMUX -LtestO$$ -f/dev/null"
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+capture()
+{
+	$OUTER capture-pane -p -t outer:0.0 2>/dev/null
+}
+
+wait_result()
+{
+	want=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		got=$($INNER show-option -gqv @result 2>/dev/null)
+		[ "$got" = "$want" ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "prompt result is '$got', expected '$want'"
+}
+
+bind_prompt()
+{
+	initial=$1
+	$INNER bind-key -n M-r command-prompt -I "$initial" -p '(word)' \
+		"set-option -g @result '%%'" || exit 1
+}
+
+run_prompt()
+{
+	want=$1
+	shift
+	$INNER set-option -g @result sentinel || exit 1
+	$OUTER send-keys M-r || exit 1
+	sleep 0.2
+	$OUTER send-keys "$@" || exit 1
+	$OUTER send-keys Enter || exit 1
+	wait_result "$want"
+}
+
+run_vi_prompt()
+{
+	want=$1
+	shift
+	$INNER set-option -g @result sentinel || exit 1
+	$OUTER send-keys M-r || exit 1
+	sleep 0.2
+	# Send Escape separately so the terminal's escape-time handling does not
+	# combine it with the first vi command as a Meta key.
+	$OUTER send-keys Escape || exit 1
+	# The inner client must see Escape as a complete key, not the prefix of a
+	# Meta sequence (the default escape-time is 500 milliseconds).
+	sleep 0.7
+	$OUTER send-keys "$@" || exit 1
+	$OUTER send-keys Enter || exit 1
+	wait_result "$want"
+}
+
+$INNER new-session -d -s prompt -x80 -y24 'exec sleep 100' || exit 1
+$INNER set-option -g status on || exit 1
+$INNER set-option -g status-position bottom || exit 1
+$INNER set-option -g window-size manual || exit 1
+$OUTER new-session -d -s outer -x80 -y24 "$INNER attach -t prompt" || exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+sleep 1
+
+# Emacs Meta-f stops after the first word; Meta-b returns to the start of the
+# previous word. Inserting a marker makes the cursor position observable.
+$INNER set-option -g status-keys emacs || exit 1
+bind_prompt 'one two'
+run_prompt 'oneX two' Home M-f X
+bind_prompt 'one two'
+run_prompt 'one Xtwo' M-b X
+
+# Vi translation and the distinct separator-aware and WORD motions.
+$INNER set-option -g status-keys vi || exit 1
+bind_prompt 'one-two three'
+run_vi_prompt 'one-two Xthree' b i X
+bind_prompt 'one-two three'
+run_vi_prompt 'one-two Xthree' B i X
+bind_prompt 'one-two three'
+run_vi_prompt 'oneX-two three' 0 w i X
+bind_prompt 'one-two three'
+run_vi_prompt 'one-two Xthree' 0 W i X
+bind_prompt 'one-two three'
+run_vi_prompt 'oneX-two three' 0 e a X
+bind_prompt 'one-two three'
+run_vi_prompt 'one-twoX three' 0 E a X
+
+# "show-" has several command matches and no longer common prefix. Tab keeps
+# the input and draws the sorted candidates inline.
+$INNER set-option -g status-keys emacs || exit 1
+bind_prompt ''
+$OUTER send-keys M-r || exit 1
+sleep 0.2
+$OUTER send-keys -l 'show-' || exit 1
+$OUTER send-keys Tab || exit 1
+sleep 0.2
+captured=$(capture)
+printf '%s\n' "$captured" | grep -Fq 'show-buffer' ||
+	fail "ambiguous completion list was not drawn"
+printf '%s\n' "$captured" | grep -Fq 'show-environment' ||
+	fail "ambiguous completion list was incomplete"
+$OUTER send-keys Escape || exit 1
+
+# Add entries to both history rings through real prompts.
+bind_prompt 'history-command'
+run_prompt 'history-command'
+$INNER bind-key -n M-s command-prompt -T search -I history-search \
+	-p '(search-history)' "set-option -g @result '%%'" || exit 1
+$OUTER send-keys M-s || exit 1
+$OUTER send-keys Enter || exit 1
+wait_result history-search
+
+command_history=$($INNER show-prompt-history -T command) || exit 1
+printf '%s\n' "$command_history" | grep -Fq 'history-command' ||
+	fail "command history entry missing"
+search_history=$($INNER show-prompt-history -T search) || exit 1
+printf '%s\n' "$search_history" | grep -Fq 'history-search' ||
+	fail "search history entry missing"
+all_history=$($INNER show-prompt-history) || exit 1
+printf '%s\n' "$all_history" | grep -Fq 'History for command:' || exit 1
+printf '%s\n' "$all_history" | grep -Fq 'History for search:' || exit 1
+
+$INNER show-prompt-history -T invalid >/dev/null 2>&1 &&
+	fail "invalid show history type succeeded"
+$INNER clear-prompt-history -T invalid >/dev/null 2>&1 &&
+	fail "invalid clear history type succeeded"
+$INNER clear-prompt-history -T command || exit 1
+$INNER show-prompt-history -T command | grep -Fq history-command &&
+	fail "type-specific history clear failed"
+$INNER clear-prompt-history || exit 1
+$INNER show-prompt-history | grep -Fq history-search &&
+	fail "all-history clear failed"
+
+exit 0