diff --git a/lib/ace/lib/dom.js b/lib/ace/lib/dom.js
index 4c5af70d..f6727078 100644
--- a/lib/ace/lib/dom.js
+++ b/lib/ace/lib/dom.js
@@ -122,7 +122,7 @@ exports.hasCssString = function(id, doc) {
 
     if (doc.createStyleSheet && (sheets = doc.styleSheets)) {
         while (index < sheets.length)
-            if (sheets[index++].title === id) return true;
+            if (sheets[index++].owningElement.id === id) return true;
     } else if ((sheets = doc.getElementsByTagName("style"))) {
         while (index < sheets.length)
             if (sheets[index++].id === id) return true;
@@ -143,7 +143,7 @@ exports.importCssString = function importCssString(cssText, id, doc) {
         style = doc.createStyleSheet();
         style.cssText = cssText;
         if (id)
-            style.title = id;
+            style.owningElement.id = id;
     } else {
         style = doc.createElementNS
             ? doc.createElementNS(XHTML_NS, "style")
@@ -289,4 +289,4 @@ exports.getParentWindow = function(document) {
     return document.defaultView || document.parentWindow;
 };
 
-});
+});
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