#customization-titlebar-visibility-button {
list-style-image: url("chrome://browser/skin/customizableui/customize-titleBar-toggle.png");
-moz-image-region: rect(0, 16px, 16px, 0);
#customization-titlebar-visibility-button {
list-style-image: url("chrome://browser/skin/customizableui/customize-titleBar-toggle.png");
-moz-image-region: rect(0, 16px, 16px, 0);