Correct condition

src/caches.lua

@@ -42,7 +42,7 @@ local function cache_groups(group, groups)
 		local tiles = def.tiles or def.tile_images
 		local texture = true_str(def.inventory_image) and def.inventory_image --or tiles[1]
 
-		if is_cube(def.drawtype) then
+		if def.drawtype and is_cube(def.drawtype) then
 			texture = get_cube(tiles)
 		elseif texture then
 			texture = texture:gsub("%^", "\\^"):gsub(":", "\\:") .. "\\^[resize\\:150x150"
@@ -55,10 +55,12 @@ local function cache_groups(group, groups)
 		end
 	end
 
-	sprite = sprite:gsub("WxH", px .. "x" .. px * c)
+	if c > 1 then
+		sprite = sprite:gsub("WxH", px .. "x" .. px * c)
 
-	i3.groups[group].sprite = sprite
-	i3.groups[group].count = c
+		i3.groups[group].sprite = sprite
+		i3.groups[group].count = c
+	end
 end
 
 local function get_item_usages(item, recipe, added)