diff --git a/lime/_backend/html5/HTML5Renderer.hx b/lime/_backend/html5/HTML5Renderer.hx
index 1eb22a2fc..60b8155a7 100644
--- a/lime/_backend/html5/HTML5Renderer.hx
+++ b/lime/_backend/html5/HTML5Renderer.hx
@@ -64,7 +64,7 @@ class HTML5Renderer {
 				
 				var options = {
 					
-					alpha: false,
+					alpha: (Reflect.hasField (parent.window.config, "background") && parent.window.config.background == null) ? true : false,
 					antialias: Reflect.hasField (parent.window.config, "antialiasing") ? parent.window.config.antialiasing > 0 : false,
 					depth: Reflect.hasField (parent.window.config, "depthBuffer") ? parent.window.config.depthBuffer : true,
 					premultipliedAlpha: false,
diff --git a/lime/app/Config.hx b/lime/app/Config.hx
index 31e705e8d..77711d4d3 100644
--- a/lime/app/Config.hx
+++ b/lime/app/Config.hx
@@ -23,7 +23,7 @@ typedef WindowConfig = {
 	
 	@:optional var allowHighDPI:Bool;
 	@:optional var antialiasing:Int;
-	@:optional var background:Int;
+	@:optional var background:Null<Int>;
 	@:optional var borderless:Bool;
 	@:optional var depthBuffer:Bool;
 	@:optional var display:Int;
diff --git a/lime/project/ProjectXMLParser.hx b/lime/project/ProjectXMLParser.hx
index 19a832fbf..e3e6d559b 100644
--- a/lime/project/ProjectXMLParser.hx
+++ b/lime/project/ProjectXMLParser.hx
@@ -1784,7 +1784,15 @@ class ProjectXMLParser extends HXProject {
 						
 					}
 					
-					windows[id].background = Std.parseInt (value);
+					if (value == "0x" || (value.length == 10 && StringTools.startsWith (value, "0x00"))) {
+						
+						windows[id].background = null;
+						
+					} else {
+						
+						windows[id].background = Std.parseInt (value);
+						
+					}
 				
 				case "orientation":
 					
diff --git a/lime/project/WindowData.hx b/lime/project/WindowData.hx
index ecff64be8..dc8d3e6a8 100644
--- a/lime/project/WindowData.hx
+++ b/lime/project/WindowData.hx
@@ -7,7 +7,7 @@ typedef WindowData = {
 	@:optional var height:Int;
 	@:optional var x:Float;
 	@:optional var y:Float;
-	@:optional var background:Int;
+	@:optional var background:Null<Int>;
 	@:optional var parameters:String;
 	@:optional var fps:Int;
 	@:optional var hardware:Bool;
diff --git a/lime/system/System.hx b/lime/system/System.hx
index 2b4e4d9d5..418b10194 100644
--- a/lime/system/System.hx
+++ b/lime/system/System.hx
@@ -67,7 +67,7 @@ class System {
 		
 		var color = null;
 		
-		if (background != null) {
+		if (background != null && background != "") {
 			
 			background = StringTools.replace (background, "#", "");
 			
diff --git a/lime/tools/platforms/HTML5Platform.hx b/lime/tools/platforms/HTML5Platform.hx
index 79654ce92..96592d239 100644
--- a/lime/tools/platforms/HTML5Platform.hx
+++ b/lime/tools/platforms/HTML5Platform.hx
@@ -169,7 +169,7 @@ class HTML5Platform extends PlatformTarget {
 		
 		var context = project.templateContext;
 		
-		context.WIN_FLASHBACKGROUND = StringTools.hex (project.window.background, 6);
+		context.WIN_FLASHBACKGROUND = project.window.background != null ? StringTools.hex (project.window.background, 6) : "";
 		context.OUTPUT_DIR = targetDirectory;
 		context.OUTPUT_FILE = outputFile;