diff --git a/OpenRA.Mods.Common/Scripting/Global/UserInterfaceGlobal.cs b/OpenRA.Mods.Common/Scripting/Global/UserInterfaceGlobal.cs
index ee10f4d643..8ae845e8d3 100644
--- a/OpenRA.Mods.Common/Scripting/Global/UserInterfaceGlobal.cs
+++ b/OpenRA.Mods.Common/Scripting/Global/UserInterfaceGlobal.cs
@@ -9,7 +9,6 @@
  */
 #endregion
 
-using System.Collections.Generic;
 using Eluant;
 using OpenRA.Mods.Common.Widgets;
 using OpenRA.Primitives;
@@ -40,7 +39,8 @@ namespace OpenRA.Mods.Common.Scripting.Global
 		{
 			if (args != null)
 			{
-				var argumentDictionary = new Dictionary<string, object>();
+				var argumentDictionary = new object[args.Count * 2];
+				var i = 0;
 				foreach (var kv in args)
 				{
 					using (kv.Key)
@@ -51,7 +51,8 @@ namespace OpenRA.Mods.Common.Scripting.Global
 								"String arguments requires a table of [\"string\"]=value pairs. " +
 								$"Received {kv.Key.WrappedClrType().Name},{kv.Value.WrappedClrType().Name}");
 
-						argumentDictionary.Add(variable, value);
+						argumentDictionary[i++] = variable;
+						argumentDictionary[i++] = value;
 					}
 				}