diff --git a/gtk2_ardour/ardour3_ui_default.conf.in b/gtk2_ardour/ardour3_ui_default.conf.in
index a1b0cc4193..ed3e6f9d9c 100644
--- a/gtk2_ardour/ardour3_ui_default.conf.in
+++ b/gtk2_ardour/ardour3_ui_default.conf.in
@@ -550,6 +550,14 @@
     <Option name="clock: text" value="6bb620ff"/>
     <Option name="clock: edited text" value="ffa500ff"/>
     <Option name="clock: cursor" value="ffa500ff"/>
+    <Option name="lock button: fill start" value="ff2714dd"/>
+    <Option name="lock button: fill end" value="8b0000ff"/>
+    <Option name="lock button: fill start active" value="202025ff"/>
+    <Option name="lock button: fill end active" value="404045ff"/>
+    <Option name="lock button: led" value="00000000"/>
+    <Option name="lock button: led active" value="00000000"/>
+    <Option name="lock button: text" value="000024ff"/>
+    <Option name="lock button: text active" value="c8c8d9ff"/>
 
     <Option name="small font" value="@FONT_SMALL@"/>
     <Option name="smaller font" value="@FONT_SMALLER@"/>
diff --git a/gtk2_ardour/canvas_vars.h b/gtk2_ardour/canvas_vars.h
index f939ee5d44..cf957630ab 100644
--- a/gtk2_ardour/canvas_vars.h
+++ b/gtk2_ardour/canvas_vars.h
@@ -237,6 +237,7 @@ BUTTON_VARS(RouteButton, "route button")
 BUTTON_VARS(MixerStripButton, "mixer strip button")
 BUTTON_VARS(MixerStripNameButton, "mixer strip name button")
 BUTTON_VARS(MidiInputButton, "midi input button")
+BUTTON_VARS(LockButton, "lock button")
 BUTTON_VARS(GenericButton, "generic button")
 
 #define CLOCK_VARS(root,name) \