diff --git a/debian/changelog b/debian/changelog
index 8e2cb536..7afb4fce 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -16,6 +16,10 @@ byobu (5.123) unreleased; urgency=medium
       set an alternate window title for their byobu session
     - https://github.com/dustinkirkland/byobu/pull/23
 
+  [ Mitsuya Shibata ]
+  * usr/bin/byobu-ctrl-a.in: LP: #1710780
+    - set prefix2 to F12 in screen-compat ctrl-a mode
+
  -- Dustin Kirkland <kirkland@ubuntu.com>  Thu, 17 Aug 2017 18:44:26 -0500
 
 byobu (5.122-0ubuntu1) artful; urgency=medium
diff --git a/usr/bin/byobu-ctrl-a.in b/usr/bin/byobu-ctrl-a.in
index e2a22941..788ea929 100755
--- a/usr/bin/byobu-ctrl-a.in
+++ b/usr/bin/byobu-ctrl-a.in
@@ -129,7 +129,7 @@ case "$bind_to" in
 				else
 					# tmux 1.6 and above supports prefix and prefix2
 					echo "set -g prefix ^${KEY}" >> "$keybindings"
-					echo "set -g prefix2 ^${KEY}" >> "$keybindings"
+					echo "set -g prefix2 F12" >> "$keybindings"
 				fi
 				echo "bind ${key} send-prefix" >> "$keybindings"
 				$BYOBU_BACKEND source "$BYOBU_PREFIX/share/byobu/profiles/tmuxrc" 2>/dev/null