diff --git a/src/static/js/ace.js b/src/static/js/ace.js
index af402dd2e..dde1134db 100644
--- a/src/static/js/ace.js
+++ b/src/static/js/ace.js
@@ -184,10 +184,10 @@ const Ace2Editor = function () {
     outerDocument.documentElement.classList.add('inner-editor', 'outerdoc', ...skinVariants);
     addStyleTagsFor(outerDocument, includedCSS);
 
-    const style = outerDocument.createElement('style');
-    style.type = 'text/css';
-    style.title = 'dynamicsyntax';
-    outerDocument.head.appendChild(style);
+    const styleO = outerDocument.createElement('style');
+    styleO.type = 'text/css';
+    styleO.title = 'dynamicsyntax';
+    outerDocument.head.appendChild(styleO);
 
     const link = outerDocument.createElement('link');
     link.rel = 'stylesheet';
@@ -196,69 +196,65 @@ const Ace2Editor = function () {
     outerDocument.head.appendChild(link);
 
     outerWindow.editorInfo = Ace2Editor.registry[info.id];
-    outerWindow.onload = () => {
-      outerWindow.onload = null;
-      const window = outerWindow;
-      const document = outerDocument;
-      setTimeout(() => {
-        const iframe = document.createElement('iframe');
-        iframe.name = 'ace_inner';
-        iframe.title = 'pad';
-        iframe.scrolling = 'no';
-        iframe.frameBorder = 0;
-        iframe.allowTransparency = true; // for IE
-        iframe.ace_outerWin = window;
-        document.body.insertBefore(iframe, document.body.firstChild);
-        window.readyFunc = () => {
-          delete window.readyFunc;
-          window.editorInfo.onEditorReady();
-          delete window.editorInfo;
-        };
-        const innerWindow = iframe.contentWindow;
-        const innerDocument = innerWindow.document;
-        innerDocument.documentElement.classList.add('inner-editor', ...skinVariants);
-        addStyleTagsFor(innerDocument, includedCSS);
+    const iframe = outerDocument.createElement('iframe');
+    iframe.name = 'ace_inner';
+    iframe.title = 'pad';
+    iframe.scrolling = 'no';
+    iframe.frameBorder = 0;
+    iframe.allowTransparency = true; // for IE
+    iframe.ace_outerWin = outerWindow;
+    const innerOnloadHandler = () => {
+      const require = window[1].frames[0].require;
+      if(!require) {
+        setTimeout(innerOnloadHandler, 10);
+      } else {
+        require.setRootURI('../javascripts/src');
+        require.setLibraryURI('../javascripts/lib');
+        require.setGlobalKeyPath('require');
 
-        const script = innerDocument.createElement('script');
-        script.type = 'text/javascript';
-        script.src = `../static/js/require-kernel.js?v=${clientVars.randomVersionString}`;
-        innerDocument.head.appendChild(script);
+        const plugins = require('ep_etherpad-lite/static/js/pluginfw/client_plugins');
+        plugins.adoptPluginsFromAncestorsOf(window);
 
-        innerWindow.onload = () => {
-          innerWindow.onload = null;
-          const window = innerWindow;
-          const require = window.require;
-          require.setRootURI('../javascripts/src');
-          require.setLibraryURI('../javascripts/lib');
-          require.setGlobalKeyPath('require');
+        const jQuery = require('ep_etherpad-lite/static/js/rjquery').jQuery;
+	window[1].frames[0].$ = jQuery;
+        const Ace2Inner = require('ep_etherpad-lite/static/js/ace2_inner');
 
-          window.plugins = require('ep_etherpad-lite/static/js/pluginfw/client_plugins');
-          window.plugins.adoptPluginsFromAncestorsOf(window);
-
-          window.$ = window.jQuery = require('ep_etherpad-lite/static/js/rjquery').jQuery;
-          window.Ace2Inner = require('ep_etherpad-lite/static/js/ace2_inner');
-
-          window.plugins.ensure(() => window.Ace2Inner.init());
-        };
-
-        const style = innerDocument.createElement('style');
-        style.type = 'text/css';
-        style.title = 'dynamicsyntax';
-        innerDocument.head.appendChild(style);
-
-        const headLines = [];
-        hooks.callAll('aceInitInnerdocbodyHead', {iframeHTML: headLines});
-        const tmp = innerDocument.createElement('div');
-        tmp.innerHTML = headLines.join('\n');
-        while (tmp.firstChild) innerDocument.head.appendChild(tmp.firstChild);
-
-        innerDocument.body.id = 'innerdocbody';
-        innerDocument.body.classList.add('innerdocbody');
-        innerDocument.body.setAttribute('role', 'application');
-        innerDocument.body.setAttribute('spellcheck', 'false');
-        innerDocument.body.appendChild(innerDocument.createTextNode('\u00A0')); //  
-      }, 0);
+        plugins.ensure(() => Ace2Inner.init());
+      }
     };
+    iframe.addEventListener('load', innerOnloadHandler);
+    outerDocument.body.insertBefore(iframe, outerDocument.body.firstChild);
+    outerWindow.readyFunc = () => {
+      delete outerWindow.readyFunc;
+      outerWindow.editorInfo.onEditorReady();
+      delete outerWindow.editorInfo;
+    };
+    const innerWindow = iframe.contentWindow;
+    const innerDocument = innerWindow.document;
+    innerDocument.documentElement.classList.add('inner-editor', ...skinVariants);
+    addStyleTagsFor(innerDocument, includedCSS);
+
+    const script = innerDocument.createElement('script');
+    script.type = 'text/javascript';
+    script.src = `../static/js/require-kernel.js?v=${clientVars.randomVersionString}`;
+    innerDocument.head.appendChild(script);
+
+    const styleI = innerDocument.createElement('style');
+    styleI.type = 'text/css';
+    styleI.title = 'dynamicsyntax';
+    innerDocument.head.appendChild(styleI);
+
+    const headLines = [];
+    hooks.callAll('aceInitInnerdocbodyHead', {iframeHTML: headLines});
+    const tmp = innerDocument.createElement('div');
+    tmp.innerHTML = headLines.join('\n');
+    while (tmp.firstChild) innerDocument.head.appendChild(tmp.firstChild);
+
+    innerDocument.body.id = 'innerdocbody';
+    innerDocument.body.classList.add('innerdocbody');
+    innerDocument.body.setAttribute('role', 'application');
+    innerDocument.body.setAttribute('spellcheck', 'false');
+    innerDocument.body.appendChild(innerDocument.createTextNode('\u00A0')); //  
 
     outerDocument.body.id = 'outerdocbody';
     outerDocument.body.classList.add('outerdocbody', ...pluginUtils.clientPluginNames());