Workaround some browsers and delete loaded compiler properly

src/app/compiler-worker.js

@@ -9,6 +9,9 @@ module.exports = function (self) {
     switch (data.cmd) {
       case 'loadVersion':
         delete self.Module;
+        // NOTE: workaround some browsers?
+        self.Module = undefined;
+
         compileJSON = null;
 
         self.importScripts(data.data);

src/app/compiler.js

@@ -144,6 +144,9 @@ function Compiler (editor, queryParams, handleGithubCall, updateFiles) {
 
   function loadInternal (url) {
     delete window.Module;
+    // NOTE: workaround some browsers?
+    window.Module = undefined;
+
     // Set a safe fallback until the new one is loaded
     setCompileJSON(function (source, optimize) {
       compilationFinished({error: 'Compiler not yet loaded.'});