diff --git a/regress/floating-pane-new-zoom.sh b/regress/floating-pane-new-zoom.sh
new file mode 100644
index 000000000..69b5cd701
--- /dev/null
+++ b/regress/floating-pane-new-zoom.sh
@@ -0,0 +1,124 @@
+#!/bin/sh
+
+# new-pane -Z must finish the zoom, including for floating panes. Check the
+# flags and the actual terminal, then unzoom and compare with an ordinary
+# floating pane to check that the saved geometry and background are restored.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+INNER="$TEST_TMUX -LtestA$$ -f/dev/null"
+OUTER="$TEST_TMUX -LtestB$$ -f/dev/null"
+DIR=$(mktemp -d) || exit 1
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0
+trap 'exit 1' 1 2 15
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+check()
+{
+	got=$($INNER display-message -p -t "$1" "$2") || exit 1
+	[ "$got" = "$3" ] || fail "$1 $2: got '$got', expected '$3'"
+}
+
+wait_capture()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p >"$DIR/capture" || exit 1
+		cmp -s "$1" "$DIR/capture" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	diff -u "$1" "$DIR/capture" >&2
+	fail "terminal did not match $1"
+}
+
+$INNER new-session -d -x 60 -y 20 'sleep 100' || exit 1
+$INNER set -g status off || exit 1
+$INNER set -g window-size manual || exit 1
+$INNER set -g default-command 'sleep 100' || exit 1
+initial=$($INNER display-message -p '#{pane_id}') || exit 1
+base=$($INNER split-window -PF '#{pane_id}' '') || exit 1
+$INNER kill-pane -t "$initial" || exit 1
+other=$($INNER split-window -h -PF '#{pane_id}' '') || exit 1
+printf 'LEFT_BASE' | $INNER display-message -I -t "$base" || exit 1
+printf 'RIGHT_BASE' | $INNER display-message -I -t "$other" || exit 1
+
+$OUTER new-session -d -x 60 -y 20 'sleep 100' || exit 1
+$OUTER set -g status off || exit 1
+$OUTER set -g default-terminal screen || exit 1
+$OUTER respawn-pane -k "$INNER attach-session" || exit 1
+
+# Build a reference with the requested floating geometry, without zoom.
+float=$($INNER new-pane -PF '#{pane_id}' -x 80% -y 80% -X 10% -Y 10% '') ||
+	exit 1
+sleep 1
+$OUTER capture-pane -p >"$DIR/floating" || exit 1
+grep -q LEFT_BASE "$DIR/floating" || fail "missing background"
+grep -q '┌' "$DIR/floating" || fail "missing floating border"
+$INNER kill-pane -t "$float" || exit 1
+
+# The zoomed pane is empty and must cover the whole terminal.
+awk 'BEGIN { for (i = 0; i < 20; i++) print "" }' >"$DIR/zoomed"
+for mode in default command empty already-zoomed; do
+	$INNER select-pane -t "$base" || exit 1
+	if [ "$mode" = already-zoomed ]; then
+		$INNER resize-pane -Z -t "$base" || exit 1
+	fi
+	case "$mode" in
+	default) set -- ;;
+	command) set -- 'sleep 100' ;;
+	*) set -- '' ;;
+	esac
+	float=$($INNER new-pane -Z -PF '#{pane_id}' \
+	    -x 80% -y 80% -X 10% -Y 10% "$@") || exit 1
+	check "$float" '#{pane_zoomed_flag}:#{window_zoomed_flag}:#{pane_floating_flag}' \
+	    '1:1:0'
+	check "$float" '#{pane_width}:#{pane_height}:#{pane_left}:#{pane_top}' \
+	    '60:20:0:0'
+	wait_capture "$DIR/zoomed"
+
+	# Output from the hidden tiled panes must not overwrite the zoomed pane.
+	printf '\033[HLEFT_BASE' | $INNER display-message -I -t "$base" || exit 1
+	printf '\033[HRIGHT_BASE' | $INNER display-message -I -t "$other" || exit 1
+	sleep 0.2
+	wait_capture "$DIR/zoomed"
+
+	$INNER resize-pane -Z -t "$float" || exit 1
+	check "$float" '#{pane_zoomed_flag}:#{window_zoomed_flag}:#{pane_floating_flag}' \
+	    '0:0:1'
+	check "$float" '#{pane_width}:#{pane_height}:#{pane_left}:#{pane_top}' \
+	    '46:14:7:3'
+	wait_capture "$DIR/floating"
+	$INNER kill-pane -t "$float" || exit 1
+done
+
+# A detached creation zooms the active pane and retains the new float's
+# requested geometry for unzooming.
+$INNER select-pane -t "$base" || exit 1
+float=$($INNER new-pane -dZ -PF '#{pane_id}' \
+    -x 80% -y 80% -X 10% -Y 10% '') || exit 1
+check "$base" '#{pane_zoomed_flag}:#{window_zoomed_flag}' '1:1'
+check "$float" '#{pane_zoomed_flag}:#{pane_active}' '0:0'
+$INNER resize-pane -Z -t "$base" || exit 1
+check "$float" '#{pane_width}:#{pane_height}:#{pane_left}:#{pane_top}' \
+    '46:14:7:3'
+wait_capture "$DIR/floating"
+$INNER kill-pane -t "$float" || exit 1
+
+exit 0