diff --git a/src/libraries/System.Private.Runtime.InteropServices.JavaScript/tests/System/Runtime/InteropServices/JavaScript/DelegateTests.cs b/src/libraries/System.Private.Runtime.InteropServices.JavaScript/tests/System/Runtime/InteropServices/JavaScript/DelegateTests.cs
index f5ef8d13a8d81..ccb9a1ade66d5 100644
--- a/src/libraries/System.Private.Runtime.InteropServices.JavaScript/tests/System/Runtime/InteropServices/JavaScript/DelegateTests.cs
+++ b/src/libraries/System.Private.Runtime.InteropServices.JavaScript/tests/System/Runtime/InteropServices/JavaScript/DelegateTests.cs
@@ -36,7 +36,7 @@ public static void InvokeFunctionInLoopUsingConstanceValues()
             Runtime.InvokeJS(@"
                 var funcDelegate = App.call_test_method (""CreateFunctionDelegate"", [  ]);
                 var res = funcDelegate (10, 20);
-                for (x = 0; x < 1000; x++)
+                for (let x = 0; x < 1000; x++)
                 {
                     res = funcDelegate (10, 20);
                 }
@@ -55,7 +55,7 @@ public static void InvokeFunctionInLoopUsingIncrementedValues()
             Runtime.InvokeJS(@"
                 var funcDelegate = App.call_test_method (""CreateFunctionDelegate"", [  ]);
                 var res = funcDelegate (10, 20);
-                for (x = 0; x < 1000; x++)
+                for (let x = 0; x < 1000; x++)
                 {
                     res = funcDelegate (x, x);
                 }
diff --git a/src/mono/sample/mbr/browser/runtime.js b/src/mono/sample/mbr/browser/runtime.js
index 74781179a31f8..41989feb6a547 100644
--- a/src/mono/sample/mbr/browser/runtime.js
+++ b/src/mono/sample/mbr/browser/runtime.js
@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+"use strict";
 var Module = { 
     config: null,
 
diff --git a/src/mono/sample/wasm/browser-bench/runtime.js b/src/mono/sample/wasm/browser-bench/runtime.js
index f9bdf8b3af7ab..87fb6436dbc1d 100644
--- a/src/mono/sample/wasm/browser-bench/runtime.js
+++ b/src/mono/sample/wasm/browser-bench/runtime.js
@@ -1,5 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
+
+"use strict";
 var Module = { 
     config: null,
 
diff --git a/src/mono/sample/wasm/browser-profile/runtime.js b/src/mono/sample/wasm/browser-profile/runtime.js
index f0636985d0358..cd0dd0cb9ed32 100644
--- a/src/mono/sample/wasm/browser-profile/runtime.js
+++ b/src/mono/sample/wasm/browser-profile/runtime.js
@@ -1,5 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
+
+"use strict";
 var Module = { 
     is_testing: false,
     config: null,
diff --git a/src/mono/sample/wasm/browser/runtime.js b/src/mono/sample/wasm/browser/runtime.js
index 816136acf36b6..904ca19958f76 100644
--- a/src/mono/sample/wasm/browser/runtime.js
+++ b/src/mono/sample/wasm/browser/runtime.js
@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+"use strict";
 var Module = { 
 
     config: null,
diff --git a/src/mono/wasm/debugger/tests/debugger-test/other.js b/src/mono/wasm/debugger/tests/debugger-test/other.js
index c32eaa064b033..72cb80bf2fe6e 100644
--- a/src/mono/wasm/debugger/tests/debugger-test/other.js
+++ b/src/mono/wasm/debugger/tests/debugger-test/other.js
@@ -1,6 +1,8 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+"use strict";
+
 function big_array_js_test (len) {
 	var big = new Array(len);
 	for (let i=0; i < len; i ++) {
diff --git a/src/mono/wasm/debugger/tests/debugger-test/runtime-debugger.js b/src/mono/wasm/debugger/tests/debugger-test/runtime-debugger.js
index 2c24917f62033..93736bfc75788 100644
--- a/src/mono/wasm/debugger/tests/debugger-test/runtime-debugger.js
+++ b/src/mono/wasm/debugger/tests/debugger-test/runtime-debugger.js
@@ -1,6 +1,8 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+"use strict";
+
 var Module = {
     config: null,
 
diff --git a/src/mono/wasm/runtime-test.js b/src/mono/wasm/runtime-test.js
index e4e7c88896bf0..76c02dfe63f85 100644
--- a/src/mono/wasm/runtime-test.js
+++ b/src/mono/wasm/runtime-test.js
@@ -1,7 +1,10 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
 // -*- mode: js; js-indent-level: 4; -*-
 //
 // Run runtime tests under a JS shell or a browser
 //
+"use strict";
 
 //glue code to deal with the differences between chrome, ch, d8, jsc and sm.
 var is_browser = typeof window != "undefined";
@@ -13,9 +16,36 @@ if (typeof (console) === "undefined") {
 		clear: function () { }
 	};
 }
-
 globalThis.testConsole = console;
 
+//define arguments for later
+var allRuntimeArguments = null;
+try {
+	if (is_browser) {
+		// We expect to be run by tests/runtime/run.js which passes in the arguments using http parameters
+		const url = new URL(decodeURI(window.location));
+		allRuntimeArguments = [];
+		for (let param of url.searchParams) {
+			if (param[0] == "arg") {
+				allRuntimeArguments.push(param[1]);
+			}
+		}
+
+	} else if (typeof arguments !== "undefined" && typeof arguments !== "null") {
+		allRuntimeArguments = arguments;
+	} else if (typeof process !== 'undefined' && typeof process.argv !== "undefined") {
+		allRuntimeArguments = process.argv.slice(2);
+	} else if (typeof scriptArgs !== "undefined") {
+		allRuntimeArguments = scriptArgs;
+	} else if (typeof WScript !== "undefined" && WScript.Arguments) {
+		allRuntimeArguments = WScript.Arguments;
+	} else {
+		allRuntimeArguments = [];
+	}
+} catch (e) {
+	console.log(e);
+}
+
 function proxyMethod (prefix, func, asJson) {
 	return function() {
 		const args = [...arguments];
@@ -66,15 +96,6 @@ if (is_browser) {
 	consoleWebSocket.onerror = function(event) {
 		console.log(`websocket error: ${event}`);
 	};
-
-	// We expect to be run by tests/runtime/run.js which passes in the arguments using http parameters
-	var url = new URL (decodeURI (window.location));
-	arguments = [];
-	for (var v of url.searchParams) {
-		if (v [0] == "arg") {
-			arguments.push (v [1]);
-		}
-	}
 }
 //proxyJson(console.log);
 
@@ -103,30 +124,8 @@ if (typeof performance == 'undefined') {
 	}
 }
 
-try {
-	if (typeof arguments == "undefined")
-		arguments = WScript.Arguments;
-	load = WScript.LoadScriptFile;
-	read = WScript.LoadBinaryFile;
-} catch (e) {
-}
-
-try {
-	if (typeof arguments == "undefined") {
-		if (typeof scriptArgs !== "undefined")
-			arguments = scriptArgs;
-	}
-} catch (e) {
-}
-
-if (arguments === undefined)
-	arguments = [];
-
 //end of all the nice shell glue code.
 
-// set up a global variable to be accessed in App.init
-var testArguments = arguments;
-
 function test_exit (exit_code) {
 	if (is_browser) {
 		// Notify the selenium script
@@ -156,44 +155,42 @@ function inspect_object (o) {
 }
 
 // Preprocess arguments
-var args = testArguments;
-console.info("Arguments: " + testArguments);
-profilers = [];
-setenv = {};
-runtime_args = [];
-enable_gc = true;
-enable_zoneinfo = false;
-working_dir='/';
-while (args !== undefined && args.length > 0) {
-	if (args [0].startsWith ("--profile=")) {
-		var arg = args [0].substring ("--profile=".length);
+console.info("Arguments: " + allRuntimeArguments);
+var profilers = [];
+var setenv = {};
+var runtime_args = [];
+var enable_gc = true;
+var enable_zoneinfo = false;
+var working_dir='/';
+while (allRuntimeArguments !== undefined && allRuntimeArguments.length > 0) {
+	if (allRuntimeArguments [0].startsWith ("--profile=")) {
+		var arg = allRuntimeArguments [0].substring ("--profile=".length);
 
 		profilers.push (arg);
 
-		args = args.slice (1);
-	} else if (args [0].startsWith ("--setenv=")) {
-		var arg = args [0].substring ("--setenv=".length);
+		allRuntimeArguments = allRuntimeArguments.slice (1);
+	} else if (allRuntimeArguments [0].startsWith ("--setenv=")) {
+		var arg = allRuntimeArguments [0].substring ("--setenv=".length);
 		var parts = arg.split ('=');
-		if (parts.length < 2)
-			fail_exec ("Error: malformed argument: '" + args [0]);
-		setenv [parts [0]] = arg.substring (parts [0].length + 1);
-		args = args.slice (1);
-	} else if (args [0].startsWith ("--runtime-arg=")) {
-		var arg = args [0].substring ("--runtime-arg=".length);
-		runtime_args.push (arg);
-		args = args.slice (1);
-	} else if (args [0] == "--disable-on-demand-gc") {
+		if (parts.length != 2)
+			fail_exec ("Error: malformed argument: '" + allRuntimeArguments [0]);
+		setenv [parts [0]] = parts [1];
+		allRuntimeArguments = allRuntimeArguments.slice (1);
+	} else if (allRuntimeArguments [0].startsWith ("--runtime-arg=")) {
+		var arg = allRuntimeArguments [0].substring ("--runtime-arg=".length);
+		runtime_args = allRuntimeArguments.push (arg);
+		allRuntimeArguments = allRuntimeArguments.slice (1);
+	} else if (allRuntimeArguments [0] == "--disable-on-demand-gc") {
 		enable_gc = false;
-		args = args.slice (1);
-	} else if (args [0].startsWith ("--working-dir=")) {
-		var arg = args [0].substring ("--working-dir=".length);
+		allRuntimeArguments = allRuntimeArguments.slice (1);
+	} else if (allRuntimeArguments [0].startsWith ("--working-dir=")) {
+		var arg = allRuntimeArguments [0].substring ("--working-dir=".length);
 		working_dir = arg;
-		args = args.slice (1);
+		allRuntimeArguments = allRuntimeArguments.slice (1);
 	} else {
 		break;
 	}
 }
-testArguments = args;
 
 // cheap way to let the testing infrastructure know we're running in a browser context (or not)
 setenv["IsBrowserDomSupported"] = is_browser.toString().toLowerCase();
@@ -316,17 +313,17 @@ var App = {
 			init ("");
 		}
 
-		if (args.length == 0) {
+		if (allRuntimeArguments.length == 0) {
 			fail_exec ("Missing required --run argument");
 			return;
 		}
 
-		if (args[0] == "--regression") {
+		if (allRuntimeArguments[0] == "--regression") {
 			var exec_regression = Module.cwrap ('mono_wasm_exec_regression', 'number', ['number', 'string'])
 
 			var res = 0;
 				try {
-					res = exec_regression (10, args[1]);
+					res = exec_regression (10, allRuntimeArguments[1]);
 					Module.print ("REGRESSION RESULT: " + res);
 				} catch (e) {
 					Module.print ("ABORT: " + e);
@@ -343,23 +340,23 @@ var App = {
 		if (runtime_args.length > 0)
 			MONO.mono_wasm_set_runtime_options (runtime_args);
 
-		if (args[0] == "--run") {
+		if (allRuntimeArguments[0] == "--run") {
 			// Run an exe
-			if (args.length == 1) {
+			if (allRuntimeArguments.length == 1) {
 				fail_exec ("Error: Missing main executable argument.");
 				return;
 			}
 
-			main_assembly_name = args[1];
-			var app_args = args.slice (2);
+			var main_assembly_name = allRuntimeArguments[1];
+			var app_args = allRuntimeArguments.slice (2);
 
-			var main_argc = args.length - 2 + 1;
+			var main_argc = allRuntimeArguments.length - 2 + 1;
 			var main_argv = Module._malloc (main_argc * 4);
-			aindex = 0;
-			Module.setValue (main_argv + (aindex * 4), wasm_strdup (args [1]), "i32")
+			var aindex = 0;
+			Module.setValue (main_argv + (aindex * 4), wasm_strdup (allRuntimeArguments [1]), "i32")
 			aindex += 1;
-			for (var i = 2; i < args.length; ++i) {
-				Module.setValue (main_argv + (aindex * 4), wasm_strdup (args [i]), "i32");
+			for (var i = 2; i < allRuntimeArguments.length; ++i) {
+				Module.setValue (main_argv + (aindex * 4), wasm_strdup (allRuntimeArguments [i]), "i32");
 				aindex += 1;
 			}
 			wasm_set_main_args (main_argc, main_argv);
@@ -381,7 +378,7 @@ var App = {
 			}
 
 		} else {
-			fail_exec ("Unhandled argument: " + args [0]);
+			fail_exec ("Unhandled argument: " + allRuntimeArguments [0]);
 		}
 	},
 	call_test_method: function (method_name, args, signature) {
diff --git a/src/mono/wasm/runtime/binding_support.js b/src/mono/wasm/runtime/binding_support.js
index 11d50bfc9558b..8d51dc8014e58 100644
--- a/src/mono/wasm/runtime/binding_support.js
+++ b/src/mono/wasm/runtime/binding_support.js
@@ -1,6 +1,8 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+"use strict";
+
 var BindingSupportLib = {
 	$BINDING__postset: 'BINDING.export_functions (Module);',
 	$BINDING: {
@@ -776,6 +778,7 @@ var BindingSupportLib = {
 				case typeof js_obj === "undefined":
 					return 0;
 				case typeof js_obj === "number": {
+					let result  = null;
 					if ((js_obj | 0) === js_obj)
 						result = this._box_js_int (js_obj);
 					else if ((js_obj >>> 0) === js_obj)
@@ -1033,7 +1036,7 @@ var BindingSupportLib = {
 		},
 
 		_create_named_function: function (name, argumentNames, body, closure) {
-			var result = null, keys = null, closureArgumentList = null, closureArgumentNames = null;
+			var result = null, closureArgumentList = null, closureArgumentNames = null;
 
 			if (closure) {
 				closureArgumentNames = Object.keys (closure);
@@ -1135,7 +1138,7 @@ var BindingSupportLib = {
 
 				var conv = primitiveConverters.get (key);
 				if (!conv)
-					throw new Error ("Unknown parameter type " + type);
+					throw new Error ("Unknown parameter type " + key);
 
 				var localStep = Object.create (conv.steps[0]);
 				localStep.size = conv.size;
@@ -1185,7 +1188,7 @@ var BindingSupportLib = {
 
 			// worst-case allocation size instead of allocating dynamically, plus padding
 			var bufferSizeBytes = converter.size + (args_marshal.length * 4) + 16;
-			var rootBufferSize = args_marshal.length;
+
 			// ensure the indirect values are 8-byte aligned so that aligned loads and stores will work
 			var indirectBaseOffset = ((((args_marshal.length * 4) + 7) / 8) | 0) * 8;
 
@@ -1286,7 +1289,7 @@ var BindingSupportLib = {
 
 			body.push(");");
 
-			bodyJs = body.join ("\r\n");
+			var bodyJs = body.join ("\r\n");
 			try {
 				compiledVariadicFunction = this._create_named_function("variadic_converter_" + converterName, argumentNames, bodyJs, closure);
 				converter.compiled_variadic_function = compiledVariadicFunction;
@@ -1473,10 +1476,10 @@ var BindingSupportLib = {
 		) {
 			this._handle_exception_for_call (converter, buffer, resultRoot, exceptionRoot, argsRootBuffer);
 
+			let result = resultRoot.value;
+
 			if (is_result_marshaled)
 				result = this._unbox_mono_obj_root (resultRoot);
-			else
-				result = resultRoot.value;
 
 			this._teardown_after_call (converter, buffer, resultRoot, exceptionRoot, argsRootBuffer);
 			return result;
@@ -1615,7 +1618,7 @@ var BindingSupportLib = {
 				"return result;"
 			);
 
-			bodyJs = body.join ("\r\n");
+			var bodyJs = body.join ("\r\n");
 
 			if (friendly_name) {
 				var escapeRE = /[^A-Za-z0-9_]/g;
@@ -1865,7 +1868,6 @@ var BindingSupportLib = {
 					js_obj[property] = js_value;
 					result = true;
 				}
-
 			}
 			return BINDING._box_js_bool (result);
 		} finally {
diff --git a/src/mono/wasm/runtime/dotnet_support.js b/src/mono/wasm/runtime/dotnet_support.js
index 3272b714eca90..f19328d9bfb3e 100644
--- a/src/mono/wasm/runtime/dotnet_support.js
+++ b/src/mono/wasm/runtime/dotnet_support.js
@@ -1,6 +1,8 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+"use strict";
+
 var DotNetSupportLib = {
 	$DOTNET: {
 		conv_string: function (mono_obj) {
@@ -46,7 +48,7 @@ var DotNetSupportLib = {
 			var funcNameJsString = DOTNET.conv_string(functionName);
 			var argsJsonJsString = argsJson && DOTNET.conv_string (argsJson);
 
-			var dotNetExports = globaThis.DotNet;
+			var dotNetExports = globalThis.DotNet;
 			if (!dotNetExports) {
 				throw new Error('The Microsoft.JSInterop.js library is not loaded.');
 			}
diff --git a/src/mono/wasm/runtime/library_mono.js b/src/mono/wasm/runtime/library_mono.js
index 1e6fc31f047da..5364d44b21a2f 100644
--- a/src/mono/wasm/runtime/library_mono.js
+++ b/src/mono/wasm/runtime/library_mono.js
@@ -1,6 +1,8 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+"use strict";
+
 /**
  * @typedef WasmId
  * @type {object}
@@ -50,26 +52,36 @@
 var MonoSupportLib = {
 	$MONO__postset: 'MONO.export_functions (Module);',
 	$MONO: {
+		active_frames: [],
 		pump_count: 0,
 		timeout_queue: [],
 		spread_timers_maximum:0,
 		_vt_stack: [],
 		mono_wasm_runtime_is_ready : false,
 		mono_wasm_ignore_pdb_load_errors: true,
+		num_icu_assets_loaded_successfully: 0,
+		_async_method_objectId: 0,
+		_next_id_var: 0,
+		_next_call_function_res_id: 0,
+		_scratch_root_buffer: null,
+		_scratch_root_free_indices: null,
+		_scratch_root_free_indices_count: 0,
+		_scratch_root_free_instances: [],
+		_vt_stack: [],
 
 		/** @type {object.<string, object>} */
 		_id_table: {},
 
 		pump_message: function () {
-			if (!this.mono_background_exec)
-				this.mono_background_exec = Module.cwrap ("mono_background_exec", null);
+			if (!MONO.mono_background_exec)
+				MONO.mono_background_exec = Module.cwrap ("mono_background_exec", null);
 			while (MONO.timeout_queue.length > 0) {
 				--MONO.pump_count;
 				MONO.timeout_queue.shift()();
 			}
 			while (MONO.pump_count > 0) {
 				--MONO.pump_count;
-				this.mono_background_exec ();
+				MONO.mono_background_exec ();
 			}
 		},
 
@@ -250,11 +262,6 @@ var MonoSupportLib = {
 			}
 		},
 
-		_scratch_root_buffer: null,
-		_scratch_root_free_indices: null,
-		_scratch_root_free_indices_count: 0,
-		_scratch_root_free_instances: [],
-
 		_mono_wasm_root_prototype: {
 			/** @returns {NativePointer} */
 			get_address: function () {
@@ -300,20 +307,20 @@ var MonoSupportLib = {
 			if (index === undefined)
 				return;
 
-			this._scratch_root_buffer.set (index, 0);
-			this._scratch_root_free_indices[this._scratch_root_free_indices_count] = index;
-			this._scratch_root_free_indices_count++;
+			MONO._scratch_root_buffer.set (index, 0);
+			MONO._scratch_root_free_indices[MONO._scratch_root_free_indices_count] = index;
+			MONO._scratch_root_free_indices_count++;
 		},
 
 		_mono_wasm_claim_scratch_index: function () {
-			if (!this._scratch_root_buffer) {
+			if (!MONO._scratch_root_buffer) {
 				const maxScratchRoots = 8192;
-				this._scratch_root_buffer = this.mono_wasm_new_root_buffer (maxScratchRoots, "js roots");
+				MONO._scratch_root_buffer = this.mono_wasm_new_root_buffer (maxScratchRoots, "js roots");
 
-				this._scratch_root_free_indices = new Int32Array (maxScratchRoots);
-				this._scratch_root_free_indices_count = maxScratchRoots;
+				MONO._scratch_root_free_indices = new Int32Array (maxScratchRoots);
+				MONO._scratch_root_free_indices_count = maxScratchRoots;
 				for (var i = 0; i < maxScratchRoots; i++)
-					this._scratch_root_free_indices[i] = maxScratchRoots - i - 1;
+					MONO._scratch_root_free_indices[i] = maxScratchRoots - i - 1;
 
 				Object.defineProperty (this._mono_wasm_root_prototype, "value", {
 					get: this._mono_wasm_root_prototype.get,
@@ -322,11 +329,11 @@ var MonoSupportLib = {
 				});
 			}
 
-			if (this._scratch_root_free_indices_count < 1)
+			if (MONO._scratch_root_free_indices_count < 1)
 				throw new Error ("Out of scratch root space");
 
-			var result = this._scratch_root_free_indices[this._scratch_root_free_indices_count - 1];
-			this._scratch_root_free_indices_count--;
+			var result = MONO._scratch_root_free_indices[MONO._scratch_root_free_indices_count - 1];
+			MONO._scratch_root_free_indices_count--;
 			return result;
 		},
 
@@ -423,11 +430,11 @@ var MonoSupportLib = {
 		mono_wasm_new_root: function (value) {
 			var result;
 
-			if (this._scratch_root_free_instances.length > 0) {
-				result = this._scratch_root_free_instances.pop ();
+			if (MONO._scratch_root_free_instances.length > 0) {
+				result = MONO._scratch_root_free_instances.pop ();
 			} else {
 				var index = this._mono_wasm_claim_scratch_index ();
-				var buffer = this._scratch_root_buffer;
+				var buffer = MONO._scratch_root_buffer;
 
 				result = Object.create (this._mono_wasm_root_prototype);
 				result.__buffer = buffer;
@@ -488,7 +495,6 @@ var MonoSupportLib = {
 			}
 		},
 
-		mono_text_decoder: undefined,
 		string_decoder: {
 			copy: function (mono_string) {
 				if (mono_string === 0)
@@ -677,7 +683,7 @@ var MonoSupportLib = {
 		},
 
 		_cache_call_function_res: function (obj) {
-			const id = `dotnet:cfo_res:${this._next_call_function_res_id++}`;
+			const id = `dotnet:cfo_res:${MONO._next_call_function_res_id++}`;
 			this._call_function_res_cache[id] = obj;
 			return id;
 		},
@@ -772,8 +778,8 @@ var MonoSupportLib = {
 		},
 
 		_clear_per_step_state: function () {
-			this._next_id_var = 0;
-			this._id_table = {};
+			MONO._next_id_var = 0;
+			MONO._id_table = {};
 		},
 
 		mono_wasm_debugger_resume: function () {
@@ -823,11 +829,11 @@ var MonoSupportLib = {
 		},
 
 		mono_wasm_runtime_ready: function () {
-			this.mono_wasm_runtime_is_ready = true;
+			MONO.mono_wasm_runtime_is_ready = true;
 			this._clear_per_step_state ();
 
 			// FIXME: where should this go?
-			this._next_call_function_res_id = 0;
+			MONO._next_call_function_res_id = 0;
 			this._call_function_res_cache = {};
 
 			this._c_fn_table = {};
@@ -1109,15 +1115,13 @@ var MonoSupportLib = {
 			return memoryOffset;
 		},
 
-		num_icu_assets_loaded_successfully: 0,
-
 		// @offset must be the address of an ICU data archive in the native heap.
 		// returns true on success.
 		mono_wasm_load_icu_data: function (offset) {
 			var fn = Module.cwrap ('mono_wasm_load_icu_data', 'number', ['number']);
 			var ok = (fn (offset)) === 1;
 			if (ok)
-				this.num_icu_assets_loaded_successfully++;
+				MONO.num_icu_assets_loaded_successfully++;
 			return ok;
 		},
 
@@ -1320,7 +1324,7 @@ var MonoSupportLib = {
 				invariantMode = true;
 
 			if (!invariantMode) {
-				if (this.num_icu_assets_loaded_successfully > 0) {
+				if (MONO.num_icu_assets_loaded_successfully > 0) {
 					console.debug ("MONO_WASM: ICU data archive(s) loaded, disabling invariant mode");
 				} else if (globalization_mode !== "icu") {
 					console.debug ("MONO_WASM: ICU data archive(s) not loaded, using invariant globalization mode");
@@ -1378,7 +1382,7 @@ var MonoSupportLib = {
 
 			var manifest;
 			try {
-				manifestContent = Module.UTF8ArrayToString(data, 8, manifestSize);
+				var manifestContent = Module.UTF8ArrayToString(data, 8, manifestSize);
 				manifest = JSON.parse(manifestContent);
 				if (!(manifest instanceof Array))
 					return false;
@@ -1405,7 +1409,7 @@ var MonoSupportLib = {
 				Module['FS_createPath'](prefix, folder, true, true);
 			});
 
-			for (row of manifest) {
+			for (var row of manifest) {
 				var name = row[0];
 				var length = row[1];
 				var bytes = data.slice(0, length);
diff --git a/src/mono/wasm/wasm.proj b/src/mono/wasm/wasm.proj
index 3eacc3e1307c1..372da1005bee2 100644
--- a/src/mono/wasm/wasm.proj
+++ b/src/mono/wasm/wasm.proj
@@ -70,6 +70,8 @@
       <_EmccCommonFlags Include="-s &quot;EXPORTED_FUNCTIONS=['_putchar']&quot;" />
       <_EmccCommonFlags Include="--source-map-base http://example.com" />
 
+      <_EmccCommonFlags Include="-s STRICT_JS=1" />      
+
       <_EmccCommonFlags Include="-s MODULARIZE=1" Condition="'$(WasmEnableES6)' != 'false'" />
       <_EmccCommonFlags Include="-s EXPORT_ES6=1" Condition="'$(WasmEnableES6)' != 'false'" />
     </ItemGroup>