1 files changed, 1 insertions, 1 deletions
diff --git a/addons/web_editor/static/src/js/editor/transcoder.js b/addons/web_editor/static/src/js/editor/transcoder.js
index 11d23bf603b..c90d5ebab1d 100644
--- a/addons/web_editor/static/src/js/editor/transcoder.js
+++ b/addons/web_editor/static/src/js/editor/transcoder.js
@@ -18,7 +18,7 @@ function getMatchedCSSRules(a) {
         var sheets = document.styleSheets;
         for (i = sheets.length-1 ; i >= 0 ; i--) {
             var rules;
-            if (sheets[i].rules) {
+            if (sheets[i].hasOwnProperty('rules')) {
                 rules = sheets[i].rules;
             } else {
                 // try...catch because Firefox not able to enumerate