diff --git a/src/common/surface.c b/src/common/surface.c
index d135bb73..712a1e50 100644
--- a/src/common/surface.c
+++ b/src/common/surface.c
@@ -1211,6 +1211,7 @@ guac_common_surface* guac_common_surface_alloc(guac_client* client,
     surface->socket = socket;
     surface->layer = layer;
     surface->parent = GUAC_DEFAULT_LAYER;
+    surface->opacity = 0xFF;
     surface->width = w;
     surface->height = h;