diff --git a/engine.c b/engine.c
index 0c459ccb..6b4d5125 100644
--- a/engine.c
+++ b/engine.c
@@ -69,7 +69,7 @@ char * Menu_tooltip[NB_BUTTONS]=
   "Layerbar / Hide menu    ",
 
   "Layers manager          ",
-  "Select transparent color",
+  "Get/Set transparent col.",
   "Merge layer             ",
   "Add layer               ",
   "Drop layer              ",
diff --git a/layers.c b/layers.c
index c3b319a7..45776c5f 100644
--- a/layers.c
+++ b/layers.c
@@ -134,20 +134,32 @@ void Button_Layer_remove(void)
 
 void Button_Layer_select(void)
 {
-  word layer;
+  short layer;
   // Determine which button is clicked according to mouse position
   layer = (Mouse_X/Menu_factor_X - Menu_bars[MENUBAR_LAYERS].Skin_width)
     / Layer_button_width;
-  
+
+  // Safety required because the mouse cursor can have slided outside button.
+  if (layer < 0)
+    layer=0;
+  else if (layer > Main_backups->Pages->Nb_layers-1)
+    layer=Main_backups->Pages->Nb_layers-1;
+
   Layer_activate(layer, LEFT_SIDE);
 }
 
 void Button_Layer_toggle(void)
 {
-  word layer;
+  short layer;
   // Determine which button is clicked according to mouse position
   layer = (Mouse_X/Menu_factor_X - Menu_bars[MENUBAR_LAYERS].Skin_width)
     / Layer_button_width;
+
+  // Safety required because the mouse cursor can have slided outside button.
+  if (layer < 0)
+    layer=0;
+  else if (layer > Main_backups->Pages->Nb_layers-1)
+    layer=Main_backups->Pages->Nb_layers-1;
   
   Layer_activate(layer, RIGHT_SIDE);
 }
diff --git a/windows.c b/windows.c
index 4186264d..de32a471 100644
--- a/windows.c
+++ b/windows.c
@@ -460,6 +460,9 @@ void Display_layerbar(void)
   word current_button;
   word repeats=1;
   
+  if (! Menu_bars[MENUBAR_LAYERS].Visible)
+    return;
+  
   // Find top
   for (current_menu = MENUBAR_COUNT - 1; current_menu > MENUBAR_LAYERS; current_menu --)
   {