--- src/desktop-style.cpp
+++ src/desktop-style.cpp
@@ -474,7 +474,7 @@
 
         if (paint_res->set && paint_effectively_set && paint->type == SP_PAINT_TYPE_COLOR) {
 
-            gfloat d[3];
+            gfloat d[4];
             sp_color_get_rgb_floatv (&paint->value.color, d);
 
             // Check if this color is the same as previous