diff --git a/common/modules/polyfill.jsm b/common/modules/polyfill.jsm
index a18acc43..829d7ef8 100644
--- a/common/modules/polyfill.jsm
+++ b/common/modules/polyfill.jsm
@@ -67,4 +67,8 @@
             for (let [i, value] of this.entries())
                 yield value;
         };
+
+    if (!String.prototype.includes)
+        String.prototype.includes = String.prototype.contains;
+
 }